diff --git a/src/cyrsasl.erl b/src/cyrsasl.erl
index cc03a49ce..21fbc9660 100644
--- a/src/cyrsasl.erl
+++ b/src/cyrsasl.erl
@@ -132,7 +132,7 @@ register_mechanism(Mechanism, Module, PasswordType) ->
 %%    end.
 
 check_credentials(_State, Props) ->
-    User = proplists:get_value(username, Props, <<>>),
+    User = proplists:get_value(authzid, Props, <<>>),
     case jid:nodeprep(User) of
       error -> {error, <<"not-authorized">>};
       <<"">> -> {error, <<"not-authorized">>};
diff --git a/src/cyrsasl_digest.erl b/src/cyrsasl_digest.erl
index 976e49e85..e58cb3035 100644
--- a/src/cyrsasl_digest.erl
+++ b/src/cyrsasl_digest.erl
@@ -50,7 +50,7 @@
                 username = <<"">> :: binary(),
                 authzid = <<"">> :: binary(),
                 get_password = fun(_) -> {false, <<>>} end :: get_password_fun(),
-                check_password = fun(_, _, _, _) -> false end :: check_password_fun(),
+                check_password = fun(_, _, _, _, _) -> false end :: check_password_fun(),
                 auth_module :: atom(),
                 host = <<"">> :: binary(),
                 hostfqdn = <<"">> :: binary()}).
@@ -83,9 +83,7 @@ mech_step(#state{step = 3, nonce = Nonce} = State,
       bad -> {error, <<"bad-protocol">>};
       KeyVals ->
 	  DigestURI = proplists:get_value(<<"digest-uri">>, KeyVals, <<>>),
-	  %DigestURI = fxml:get_attr_s(<<"digest-uri">>, KeyVals),
 	  UserName = proplists:get_value(<<"username">>, KeyVals, <<>>),
-	  %UserName = fxml:get_attr_s(<<"username">>, KeyVals),
 	  case is_digesturi_valid(DigestURI, State#state.host,
 				  State#state.hostfqdn)
 	      of
@@ -97,13 +95,11 @@ mech_step(#state{step = 3, nonce = Nonce} = State,
 		{error, <<"not-authorized">>, UserName};
 	    true ->
 		AuthzId = proplists:get_value(<<"authzid">>, KeyVals, <<>>),
-		%AuthzId = fxml:get_attr_s(<<"authzid">>, KeyVals),
 		case (State#state.get_password)(UserName) of
 		  {false, _} -> {error, <<"not-authorized">>, UserName};
 		  {Passwd, AuthModule} ->
-		      case (State#state.check_password)(UserName, <<"">>,
+		      case (State#state.check_password)(UserName, UserName, <<"">>,
 		                    proplists:get_value(<<"response">>, KeyVals, <<>>),
-							%fxml:get_attr_s(<<"response">>, KeyVals),
 							fun (PW) ->
 								response(KeyVals,
 									 UserName,
@@ -130,7 +126,11 @@ mech_step(#state{step = 5, auth_module = AuthModule,
 		 username = UserName, authzid = AuthzId},
 	  <<"">>) ->
     {ok,
-     [{username, UserName}, {authzid, AuthzId},
+     [{username, UserName}, {authzid, case AuthzId of
+        <<"">> -> UserName;
+        _ -> AuthzId
+      end
+    },
       {auth_module, AuthModule}]};
 mech_step(A, B) ->
     ?DEBUG("SASL DIGEST: A ~p B ~p", [A, B]),
diff --git a/src/cyrsasl_plain.erl b/src/cyrsasl_plain.erl
index a9c1de056..82d68f87f 100644
--- a/src/cyrsasl_plain.erl
+++ b/src/cyrsasl_plain.erl
@@ -45,7 +45,7 @@ mech_new(_Host, _GetPassword, CheckPassword, _CheckPasswordDigest) ->
 mech_step(State, ClientIn) ->
     case prepare(ClientIn) of
       [AuthzId, User, Password] ->
-	  case (State#state.check_password)(User, Password) of
+	  case (State#state.check_password)(User, AuthzId, Password) of
 	    {true, AuthModule} ->
 		{ok,
 		 [{username, User}, {authzid, AuthzId},
@@ -60,12 +60,17 @@ prepare(ClientIn) ->
       [<<"">>, UserMaybeDomain, Password] ->
 	  case parse_domain(UserMaybeDomain) of
 	    %% <NUL>login@domain<NUL>pwd
-	    [User, _Domain] -> [UserMaybeDomain, User, Password];
+	    [User, _Domain] -> [User, User, Password];
 	    %% <NUL>login<NUL>pwd
-	    [User] -> [<<"">>, User, Password]
+	    [User] -> [User, User, Password]
 	  end;
+      [AuthzId, User, Password] ->
+      case parse_domain(AuthzId) of
       %% login@domain<NUL>login<NUL>pwd
-      [AuthzId, User, Password] -> [AuthzId, User, Password];
+        [AuthzUser, _Domain] -> [AuthzUser, User, Password];
+        %% login<NUL>login<NUL>pwd
+        [AuthzUser] -> [AuthzUser, User, Password]
+      end;
       _ -> error
     end.
 
diff --git a/src/ejabberd_auth.erl b/src/ejabberd_auth.erl
index 2cc37c6e0..343ad9436 100644
--- a/src/ejabberd_auth.erl
+++ b/src/ejabberd_auth.erl
@@ -32,9 +32,9 @@
 -author('alexey@process-one.net').
 
 %% External exports
--export([start/0, set_password/3, check_password/3,
-	 check_password/5, check_password_with_authmodule/3,
-	 check_password_with_authmodule/5, try_register/3,
+-export([start/0, set_password/3, check_password/4,
+	 check_password/6, check_password_with_authmodule/4,
+	 check_password_with_authmodule/6, try_register/3,
 	 dirty_get_registered_users/0, get_vh_registered_users/1,
 	 get_vh_registered_users/2, export/1, import/1,
 	 get_vh_registered_users_number/1, import/3,
@@ -63,8 +63,8 @@
 -callback remove_user(binary(), binary()) -> any().
 -callback remove_user(binary(), binary(), binary()) -> any().
 -callback is_user_exists(binary(), binary()) -> boolean() | {error, atom()}.
--callback check_password(binary(), binary(), binary()) -> boolean().
--callback check_password(binary(), binary(), binary(), binary(),
+-callback check_password(binary(), binary(), binary(), binary()) -> boolean().
+-callback check_password(binary(), binary(), binary(), binary(), binary(),
                          fun((binary()) -> binary())) -> boolean().
 -callback try_register(binary(), binary(), binary()) -> {atomic, atom()} |
                                                         {error, atom()}.
@@ -102,10 +102,10 @@ store_type(Server) ->
 		end,
 		plain, auth_modules(Server)).
 
--spec check_password(binary(), binary(), binary()) -> boolean().
+-spec check_password(binary(), binary(), binary(), binary()) -> boolean().
 
-check_password(User, Server, Password) ->
-    case check_password_with_authmodule(User, Server,
+check_password(User, AuthzId, Server, Password) ->
+    case check_password_with_authmodule(User, AuthzId, Server,
 					Password)
 	of
       {true, _AuthModule} -> true;
@@ -113,15 +113,15 @@ check_password(User, Server, Password) ->
     end.
 
 %% @doc Check if the user and password can login in server.
-%% @spec (User::string(), Server::string(), Password::string(),
+%% @spec (User::string(), AuthzId::string(), Server::string(), Password::string(),
 %%        Digest::string(), DigestGen::function()) ->
 %%     true | false
--spec check_password(binary(), binary(), binary(), binary(),
+-spec check_password(binary(), binary(), binary(), binary(), binary(),
                      fun((binary()) -> binary())) -> boolean().
                                  
-check_password(User, Server, Password, Digest,
+check_password(User, AuthzId, Server, Password, Digest,
 	       DigestGen) ->
-    case check_password_with_authmodule(User, Server,
+    case check_password_with_authmodule(User, AuthzId, Server,
 					Password, Digest, DigestGen)
 	of
       {true, _AuthModule} -> true;
@@ -132,28 +132,28 @@ check_password(User, Server, Password, Digest,
 %% The user can login if at least an authentication method accepts the user
 %% and the password.
 %% The first authentication method that accepts the credentials is returned.
-%% @spec (User::string(), Server::string(), Password::string()) ->
+%% @spec (User::string(), AuthzId::string(), Server::string(), Password::string()) ->
 %%     {true, AuthModule} | false
 %% where
 %%   AuthModule = ejabberd_auth_anonymous | ejabberd_auth_external
 %%                 | ejabberd_auth_internal | ejabberd_auth_ldap
-%%                 | ejabberd_auth_odbc | ejabberd_auth_pam
--spec check_password_with_authmodule(binary(), binary(), binary()) -> false |
+%%                 | ejabberd_auth_odbc | ejabberd_auth_pam | ejabberd_auth_riak
+-spec check_password_with_authmodule(binary(), binary(), binary(), binary()) -> false |
                                                                       {true, atom()}.
 
-check_password_with_authmodule(User, Server,
+check_password_with_authmodule(User, AuthzId, Server,
 			       Password) ->
     check_password_loop(auth_modules(Server),
-			[User, Server, Password]).
+			[User, AuthzId, Server, Password]).
 
--spec check_password_with_authmodule(binary(), binary(), binary(), binary(),
+-spec check_password_with_authmodule(binary(), binary(), binary(), binary(), binary(),
                                      fun((binary()) -> binary())) -> false |
                                                                      {true, atom()}.
 
-check_password_with_authmodule(User, Server, Password,
+check_password_with_authmodule(User, AuthzId, Server, Password,
 			       Digest, DigestGen) ->
     check_password_loop(auth_modules(Server),
-			[User, Server, Password, Digest, DigestGen]).
+			[User, AuthzId, Server, Password, Digest, DigestGen]).
 
 check_password_loop([], _Args) -> false;
 check_password_loop([AuthModule | AuthModules], Args) ->
diff --git a/src/ejabberd_auth_anonymous.erl b/src/ejabberd_auth_anonymous.erl
index 7b21752a2..9c4b719c3 100644
--- a/src/ejabberd_auth_anonymous.erl
+++ b/src/ejabberd_auth_anonymous.erl
@@ -38,8 +38,8 @@
 	 unregister_connection/3
 	]).
 
--export([login/2, set_password/3, check_password/3,
-	 check_password/5, try_register/3,
+-export([login/2, set_password/3, check_password/4,
+	 check_password/6, try_register/3,
 	 dirty_get_registered_users/0, get_vh_registered_users/1,
 	 get_vh_registered_users/2,
 	 get_vh_registered_users_number/1,
@@ -175,11 +175,11 @@ purge_hook(true, LUser, LServer) ->
 
 %% When anonymous login is enabled, check the password for permenant users
 %% before allowing access
-check_password(User, Server, Password) ->
-    check_password(User, Server, Password, undefined,
+check_password(User, AuthzId, Server, Password) ->
+    check_password(User, AuthzId, Server, Password, undefined,
 		   undefined).
 
-check_password(User, Server, _Password, _Digest,
+check_password(User, _AuthzId, Server, _Password, _Digest,
 	       _DigestGen) ->
     case
       ejabberd_auth:is_user_exists_in_other_modules(?MODULE,
diff --git a/src/ejabberd_auth_external.erl b/src/ejabberd_auth_external.erl
index 2944ac3f3..5897fba5b 100644
--- a/src/ejabberd_auth_external.erl
+++ b/src/ejabberd_auth_external.erl
@@ -31,8 +31,8 @@
 
 -behaviour(ejabberd_auth).
 
--export([start/1, set_password/3, check_password/3,
-	 check_password/5, try_register/3,
+-export([start/1, set_password/3, check_password/4,
+	 check_password/6, try_register/3,
 	 dirty_get_registered_users/0, get_vh_registered_users/1,
 	 get_vh_registered_users/2,
 	 get_vh_registered_users_number/1,
@@ -76,16 +76,20 @@ plain_password_required() -> true.
 
 store_type() -> external.
 
-check_password(User, Server, Password) ->
+check_password(User, AuthzId, Server, Password) ->
+    if AuthzId /= <<>> andalso AuthzId /= User ->
+        false;
+    true ->
     case get_cache_option(Server) of
-      false -> check_password_extauth(User, Server, Password);
+          false -> check_password_extauth(User, AuthzId, Server, Password);
       {true, CacheTime} ->
-	  check_password_cache(User, Server, Password, CacheTime)
+    	  check_password_cache(User, AuthzId, Server, Password, CacheTime)
+        end
     end.
 
-check_password(User, Server, Password, _Digest,
+check_password(User, AuthzId, Server, Password, _Digest,
 	       _DigestGen) ->
-    check_password(User, Server, Password).
+    check_password(User, AuthzId, Server, Password).
 
 set_password(User, Server, Password) ->
     case extauth:set_password(User, Server, Password) of
@@ -178,8 +182,8 @@ get_cache_option(Host) ->
         CacheTime -> {true, CacheTime}
     end.
 
-%% @spec (User, Server, Password) -> true | false
-check_password_extauth(User, Server, Password) ->
+%% @spec (User, AuthzId, Server, Password) -> true | false
+check_password_extauth(User, _AuthzId, Server, Password) ->
     extauth:check_password(User, Server, Password) andalso
       Password /= <<"">>.
 
@@ -187,35 +191,35 @@ check_password_extauth(User, Server, Password) ->
 try_register_extauth(User, Server, Password) ->
     extauth:try_register(User, Server, Password).
 
-check_password_cache(User, Server, Password, 0) ->
-    check_password_external_cache(User, Server, Password);
-check_password_cache(User, Server, Password,
+check_password_cache(User, AuthzId, Server, Password, 0) ->
+    check_password_external_cache(User, AuthzId, Server, Password);
+check_password_cache(User, AuthzId, Server, Password,
 		     CacheTime) ->
     case get_last_access(User, Server) of
       online ->
-	  check_password_internal(User, Server, Password);
+	  check_password_internal(User, AuthzId, Server, Password);
       never ->
-	  check_password_external_cache(User, Server, Password);
+	  check_password_external_cache(User, AuthzId, Server, Password);
       mod_last_required ->
 	  ?ERROR_MSG("extauth is used, extauth_cache is enabled "
 		     "but mod_last is not enabled in that "
 		     "host",
 		     []),
-	  check_password_external_cache(User, Server, Password);
+	  check_password_external_cache(User, AuthzId, Server, Password);
       TimeStamp ->
 	  case is_fresh_enough(TimeStamp, CacheTime) of
 	    %% If no need to refresh, check password against Mnesia
 	    true ->
-		case check_password_internal(User, Server, Password) of
+		case check_password_internal(User, AuthzId, Server, Password) of
 		  %% If password valid in Mnesia, accept it
 		  true -> true;
 		  %% Else (password nonvalid in Mnesia), check in extauth and cache result
 		  false ->
-		      check_password_external_cache(User, Server, Password)
+		      check_password_external_cache(User, AuthzId, Server, Password)
 		end;
 	    %% Else (need to refresh), check in extauth and cache result
 	    false ->
-		check_password_external_cache(User, Server, Password)
+		check_password_external_cache(User, AuthzId, Server, Password)
 	  end
     end.
 
@@ -241,8 +245,8 @@ get_password_cache(User, Server, CacheTime) ->
     end.
 
 %% Check the password using extauth; if success then cache it
-check_password_external_cache(User, Server, Password) ->
-    case check_password_extauth(User, Server, Password) of
+check_password_external_cache(User, AuthzId, Server, Password) ->
+    case check_password_extauth(User, AuthzId, Server, Password) of
       true ->
 	  set_password_internal(User, Server, Password), true;
       false -> false
@@ -256,9 +260,9 @@ try_register_external_cache(User, Server, Password) ->
       _ -> {error, not_allowed}
     end.
 
-%% @spec (User, Server, Password) -> true | false
-check_password_internal(User, Server, Password) ->
-    ejabberd_auth_internal:check_password(User, Server,
+%% @spec (User, AuthzId, Server, Password) -> true | false
+check_password_internal(User, AuthzId, Server, Password) ->
+    ejabberd_auth_internal:check_password(User, AuthzId, Server,
 					  Password).
 
 %% @spec (User, Server, Password) -> ok | {error, invalid_jid}
diff --git a/src/ejabberd_auth_internal.erl b/src/ejabberd_auth_internal.erl
index d60e0fc5f..3b30b3607 100644
--- a/src/ejabberd_auth_internal.erl
+++ b/src/ejabberd_auth_internal.erl
@@ -31,8 +31,8 @@
 
 -behaviour(ejabberd_auth).
 
--export([start/1, set_password/3, check_password/3,
-	 check_password/5, try_register/3,
+-export([start/1, set_password/3, check_password/4,
+	 check_password/6, try_register/3,
 	 dirty_get_registered_users/0, get_vh_registered_users/1,
 	 get_vh_registered_users/2,
 	 get_vh_registered_users_number/1,
@@ -86,9 +86,12 @@ store_type() ->
       true -> scram %% allows: PLAIN SCRAM
     end.
 
-check_password(User, Server, Password) ->
-    LUser = jid:nodeprep(User),
-    LServer = jid:nameprep(Server),
+check_password(User, AuthzId, Server, Password) ->
+    if AuthzId /= <<>> andalso AuthzId /= User ->
+        false;
+    true ->
+        LUser = jid:nodeprep(User),
+        LServer = jid:nameprep(Server),
     US = {LUser, LServer},
     case catch mnesia:dirty_read({passwd, US}) of
       [#passwd{password = Password}]
@@ -98,12 +101,16 @@ check_password(User, Server, Password) ->
 	  when is_record(Scram, scram) ->
 	  is_password_scram_valid(Password, Scram);
       _ -> false
+        end
     end.
 
-check_password(User, Server, Password, Digest,
+check_password(User, AuthzId, Server, Password, Digest,
 	       DigestGen) ->
-    LUser = jid:nodeprep(User),
-    LServer = jid:nameprep(Server),
+    if AuthzId /= <<>> andalso AuthzId /= User ->
+        false;
+    true ->
+        LUser = jid:nodeprep(User),
+        LServer = jid:nameprep(Server),
     US = {LUser, LServer},
     case catch mnesia:dirty_read({passwd, US}) of
       [#passwd{password = Passwd}] when is_binary(Passwd) ->
@@ -125,6 +132,7 @@ check_password(User, Server, Password, Digest,
 	     true -> (Passwd == Password) and (Password /= <<"">>)
 	  end;
       _ -> false
+        end
     end.
 
 %% @spec (User::string(), Server::string(), Password::string()) ->
diff --git a/src/ejabberd_auth_ldap.erl b/src/ejabberd_auth_ldap.erl
index dd5d54a74..51b466ef4 100644
--- a/src/ejabberd_auth_ldap.erl
+++ b/src/ejabberd_auth_ldap.erl
@@ -37,7 +37,7 @@
 	 handle_cast/2, terminate/2, code_change/3]).
 
 -export([start/1, stop/1, start_link/1, set_password/3,
-	 check_password/3, check_password/5, try_register/3,
+	 check_password/4, check_password/6, try_register/3,
 	 dirty_get_registered_users/0, get_vh_registered_users/1,
 	 get_vh_registered_users/2,
 	 get_vh_registered_users_number/1,
@@ -116,7 +116,10 @@ plain_password_required() -> true.
 
 store_type() -> external.
 
-check_password(User, Server, Password) ->
+check_password(User, AuthzId, Server, Password) ->
+    if AuthzId /= <<>> andalso AuthzId /= User ->
+        false;
+    true ->
     if Password == <<"">> -> false;
        true ->
 	   case catch check_password_ldap(User, Server, Password)
@@ -124,11 +127,12 @@ check_password(User, Server, Password) ->
 	     {'EXIT', _} -> false;
 	     Result -> Result
 	   end
+        end
     end.
 
-check_password(User, Server, Password, _Digest,
+check_password(User, AuthzId, Server, Password, _Digest,
 	       _DigestGen) ->
-    check_password(User, Server, Password).
+    check_password(User, AuthzId, Server, Password).
 
 set_password(User, Server, Password) ->
     {ok, State} = eldap_utils:get_state(Server, ?MODULE),
diff --git a/src/ejabberd_auth_odbc.erl b/src/ejabberd_auth_odbc.erl
index 18d062012..dc3248fe8 100644
--- a/src/ejabberd_auth_odbc.erl
+++ b/src/ejabberd_auth_odbc.erl
@@ -31,8 +31,8 @@
 
 -behaviour(ejabberd_auth).
 
--export([start/1, set_password/3, check_password/3,
-	 check_password/5, try_register/3,
+-export([start/1, set_password/3, check_password/4,
+	 check_password/6, try_register/3,
 	 dirty_get_registered_users/0, get_vh_registered_users/1,
 	 get_vh_registered_users/2,
 	 get_vh_registered_users_number/1,
@@ -63,10 +63,13 @@ store_type() ->
       true -> scram %% allows: PLAIN SCRAM
     end.
 
-%% @spec (User, Server, Password) -> true | false | {error, Error}
-check_password(User, Server, Password) ->
-    LServer = jid:nameprep(Server),
-    LUser = jid:nodeprep(User),
+%% @spec (User, AuthzId, Server, Password) -> true | false | {error, Error}
+check_password(User, AuthzId, Server, Password) ->
+    if AuthzId /= <<>> andalso AuthzId /= User ->
+        false;
+    true ->
+        LServer = jid:nameprep(Server),
+        LUser = jid:nodeprep(User),
     if (LUser == error) or (LServer == error) ->
             false;
        (LUser == <<>>) or (LServer == <<>>) ->
@@ -106,13 +109,17 @@ check_password(User, Server, Password) ->
                             false %% Typical error is database not accessible
                     end
             end
+        end
     end.
 
-%% @spec (User, Server, Password, Digest, DigestGen) -> true | false | {error, Error}
-check_password(User, Server, Password, Digest,
+%% @spec (User, AuthzId, Server, Password, Digest, DigestGen) -> true | false | {error, Error}
+check_password(User, AuthzId, Server, Password, Digest,
 	       DigestGen) ->
-    LServer = jid:nameprep(Server),
-    LUser = jid:nodeprep(User),
+    if AuthzId /= <<>> andalso AuthzId /= User ->
+        false;
+    true ->
+        LServer = jid:nameprep(Server),
+        LUser = jid:nodeprep(User),
     if (LUser == error) or (LServer == error) ->
             false;
        (LUser == <<>>) or (LServer == <<>>) ->
@@ -141,6 +148,7 @@ check_password(User, Server, Password, Digest,
                 true ->
                     false
             end
+        end
     end.
 
 %% @spec (User::string(), Server::string(), Password::string()) ->
@@ -359,7 +367,7 @@ remove_user(User, Server, Password) ->
        true ->
             case is_scrammed() of
                 true ->
-                    case check_password(User, Server, Password) of
+                    case check_password(User, <<"">>, Server, Password) of
                         true ->
                             remove_user(User, Server),
                             ok;
diff --git a/src/ejabberd_auth_pam.erl b/src/ejabberd_auth_pam.erl
index ee5123c5e..fa4b9f078 100644
--- a/src/ejabberd_auth_pam.erl
+++ b/src/ejabberd_auth_pam.erl
@@ -30,8 +30,8 @@
 
 -behaviour(ejabberd_auth).
 
--export([start/1, set_password/3, check_password/3,
-	 check_password/5, try_register/3,
+-export([start/1, set_password/3, check_password/4,
+	 check_password/6, try_register/3,
 	 dirty_get_registered_users/0, get_vh_registered_users/1,
 	 get_vh_registered_users/2,
 	 get_vh_registered_users_number/1,
@@ -46,11 +46,14 @@ start(_Host) ->
 set_password(_User, _Server, _Password) ->
     {error, not_allowed}.
 
-check_password(User, Server, Password, _Digest,
+check_password(User, AuthzId, Server, Password, _Digest,
 	       _DigestGen) ->
-    check_password(User, Server, Password).
+    check_password(User, AuthzId, Server, Password).
 
-check_password(User, Host, Password) ->
+check_password(User, AuthzId, Host, Password) ->
+    if AuthzId /= <<>> andalso AuthzId /= User ->
+        false;
+    true ->
     Service = get_pam_service(Host),
     UserInfo = case get_pam_userinfotype(Host) of
 		 username -> User;
@@ -61,6 +64,7 @@ check_password(User, Host, Password) ->
 	of
       true -> true;
       _ -> false
+        end
     end.
 
 try_register(_User, _Server, _Password) ->
diff --git a/src/ejabberd_auth_riak.erl b/src/ejabberd_auth_riak.erl
index 64bf12c6a..bc745fea4 100644
--- a/src/ejabberd_auth_riak.erl
+++ b/src/ejabberd_auth_riak.erl
@@ -30,8 +30,8 @@
 -behaviour(ejabberd_auth).
 
 %% External exports
--export([start/1, set_password/3, check_password/3,
-	 check_password/5, try_register/3,
+-export([start/1, set_password/3, check_password/4,
+	 check_password/6, try_register/3,
 	 dirty_get_registered_users/0, get_vh_registered_users/1,
 	 get_vh_registered_users/2,
 	 get_vh_registered_users_number/1,
@@ -66,9 +66,12 @@ store_type() ->
 passwd_schema() ->
     {record_info(fields, passwd), #passwd{}}.
 
-check_password(User, Server, Password) ->
-    LUser = jid:nodeprep(User),
-    LServer = jid:nameprep(Server),
+check_password(User, AuthzId, Server, Password) ->
+    if AuthzId /= <<>> andalso AuthzId /= User ->
+        false;
+    true ->
+        LUser = jid:nodeprep(User),
+        LServer = jid:nameprep(Server),
     case ejabberd_riak:get(passwd, passwd_schema(), {LUser, LServer}) of
         {ok, #passwd{password = Password}} when is_binary(Password) ->
             Password /= <<"">>;
@@ -76,12 +79,16 @@ check_password(User, Server, Password) ->
             is_password_scram_valid(Password, Scram);
         _ ->
             false
+        end
     end.
 
-check_password(User, Server, Password, Digest,
+check_password(User, AuthzId, Server, Password, Digest,
 	       DigestGen) ->
-    LUser = jid:nodeprep(User),
-    LServer = jid:nameprep(Server),
+    if AuthzId /= <<>> andalso AuthzId /= User ->
+        false;
+    true ->
+        LUser = jid:nodeprep(User),
+        LServer = jid:nameprep(Server),
     case ejabberd_riak:get(passwd, passwd_schema(), {LUser, LServer}) of
       {ok, #passwd{password = Passwd}} when is_binary(Passwd) ->
 	  DigRes = if Digest /= <<"">> ->
@@ -102,6 +109,7 @@ check_password(User, Server, Password, Digest,
 	     true -> (Passwd == Password) and (Password /= <<"">>)
 	  end;
       _ -> false
+        end
     end.
 
 set_password(User, Server, Password) ->
diff --git a/src/ejabberd_c2s.erl b/src/ejabberd_c2s.erl
index d58c1e1d2..936abc7a9 100644
--- a/src/ejabberd_c2s.erl
+++ b/src/ejabberd_c2s.erl
@@ -382,13 +382,13 @@ wait_for_stream({xmlstreamstart, _Name, Attrs}, StateData) ->
 						    ejabberd_auth:get_password_with_authmodule(
 							U, Server)
 					    end,
-					    fun (U, P) ->
+					  fun(U, AuthzId, P) ->
 						    ejabberd_auth:check_password_with_authmodule(
-							U, Server, P)
+						    U, AuthzId, Server, P)
 					    end,
-					    fun (U, P, D, DG) ->
+					  fun(U, AuthzId, P, D, DG) ->
 						    ejabberd_auth:check_password_with_authmodule(
-							U, Server, P, D, DG)
+						    U, AuthzId, Server, P, D, DG)
 					    end),
 				    Mechs =
 					case TLSEnabled or not TLSRequired of
@@ -634,7 +634,7 @@ wait_for_auth({xmlstreamelement, El}, StateData) ->
 		    DGen = fun (PW) ->
 			    p1_sha:sha(<<(StateData#state.streamid)/binary, PW/binary>>)
 		    end,
-		    case ejabberd_auth:check_password_with_authmodule(U,
+		case ejabberd_auth:check_password_with_authmodule(U, U,
 			    StateData#state.server,
 			    P, D, DGen)
 		    of
@@ -752,9 +752,7 @@ wait_for_feature_request({xmlstreamelement, El},
 	      of
 	    {ok, Props} ->
 		(StateData#state.sockmod):reset_stream(StateData#state.socket),
-		%U = fxml:get_attr_s(username, Props),
-		U = proplists:get_value(username, Props, <<>>),
-		%AuthModule = fxml:get_attr_s(auth_module, Props),
+		U = identity(Props),
 		AuthModule = proplists:get_value(auth_module, Props, undefined),
 		?INFO_MSG("(~w) Accepted authentication for ~s "
 			  "by ~p from ~s",
@@ -876,9 +874,7 @@ wait_for_sasl_response({xmlstreamelement, El},
 	    {ok, Props} ->
 		catch
 		  (StateData#state.sockmod):reset_stream(StateData#state.socket),
-%		U = fxml:get_attr_s(username, Props),
-		U = proplists:get_value(username, Props, <<>>),
-%		AuthModule = fxml:get_attr_s(auth_module, Props),
+		U = identity(Props),
 		AuthModule = proplists:get_value(auth_module, Props, <<>>),
 		?INFO_MSG("(~w) Accepted authentication for ~s "
 			  "by ~p from ~s",
@@ -899,9 +895,7 @@ wait_for_sasl_response({xmlstreamelement, El},
 						user = U});
 	    {ok, Props, ServerOut} ->
 		(StateData#state.sockmod):reset_stream(StateData#state.socket),
-%		U = fxml:get_attr_s(username, Props),
-		U = proplists:get_value(username, Props, <<>>),
-%		AuthModule = fxml:get_attr_s(auth_module, Props),
+		U = identity(Props),
 		AuthModule = proplists:get_value(auth_module, Props, undefined),
 		?INFO_MSG("(~w) Accepted authentication for ~s "
 			  "by ~p from ~s",
@@ -3129,6 +3123,12 @@ pack_string(String, Pack) ->
 transform_listen_option(Opt, Opts) ->
     [Opt|Opts].
 
+identity(Props) ->
+    case proplists:get_value(authzid, Props, <<>>) of
+	<<>> -> proplists:get_value(username, Props, <<>>);
+	AuthzId -> AuthzId
+    end.
+
 opt_type(domain_certfile) -> fun iolist_to_binary/1;
 opt_type(max_fsm_queue) ->
     fun (I) when is_integer(I), I > 0 -> I end;
diff --git a/src/ejabberd_commands.erl b/src/ejabberd_commands.erl
index 265d7141f..3c98316da 100644
--- a/src/ejabberd_commands.erl
+++ b/src/ejabberd_commands.erl
@@ -517,7 +517,7 @@ check_auth(Command, {User, Server, {oauth, Token}, _}) ->
     end;
 check_auth(_Command, {User, Server, Password, _}) when is_binary(Password) ->
     %% Check the account exists and password is valid
-    case ejabberd_auth:check_password(User, Server, Password) of
+    case ejabberd_auth:check_password(User, <<"">>, Server, Password) of
         true -> {ok, User, Server};
         _ -> throw({error, invalid_account_data})
     end.
diff --git a/src/ejabberd_oauth.erl b/src/ejabberd_oauth.erl
index 1925a2f78..d8e0a435d 100644
--- a/src/ejabberd_oauth.erl
+++ b/src/ejabberd_oauth.erl
@@ -134,7 +134,7 @@ authenticate_user({User, Server}, {password, Password} = Ctx) ->
                   none),
             case acl:match_rule(JID#jid.lserver, Access, JID) of
                 allow ->
-                    case ejabberd_auth:check_password(User, Server, Password) of
+                    case ejabberd_auth:check_password(User, <<"">>, Server, Password) of
                         true ->
                             {ok, {Ctx, {user, User, Server}}};
                         false ->
diff --git a/src/ejabberd_web_admin.erl b/src/ejabberd_web_admin.erl
index 11d90ab80..f525a4d39 100644
--- a/src/ejabberd_web_admin.erl
+++ b/src/ejabberd_web_admin.erl
@@ -264,7 +264,7 @@ get_auth_admin(Auth, HostHTTP, RPath, Method) ->
 
 get_auth_account(HostOfRule, AccessRule, User, Server,
 		 Pass) ->
-    case ejabberd_auth:check_password(User, Server, Pass) of
+    case ejabberd_auth:check_password(User, <<"">>, Server, Pass) of
       true ->
 	  case is_acl_match(HostOfRule, AccessRule,
 			    jid:make(User, Server, <<"">>))
diff --git a/src/mod_http_api.erl b/src/mod_http_api.erl
index 7f86d5cc1..3b7a09cb7 100644
--- a/src/mod_http_api.erl
+++ b/src/mod_http_api.erl
@@ -116,7 +116,7 @@ check_permissions(#request{auth = HTTPAuth, headers = Headers}, Command)
                     {SJID, Pass} ->
                         case jid:from_string(SJID) of
                             #jid{user = User, server = Server} ->
-                                case ejabberd_auth:check_password(User, Server, Pass) of
+                                case ejabberd_auth:check_password(User, <<"">>, Server, Pass) of
                                     true -> {ok, {User, Server, Pass, Admin}};
                                     false -> false
                                 end;
diff --git a/src/mod_proxy65_stream.erl b/src/mod_proxy65_stream.erl
index 36dd7af19..840173299 100644
--- a/src/mod_proxy65_stream.erl
+++ b/src/mod_proxy65_stream.erl
@@ -153,7 +153,7 @@ wait_for_auth(Packet,
 	      #state{socket = Socket, host = Host} = StateData) ->
     case mod_proxy65_lib:unpack_auth_request(Packet) of
       {User, Pass} ->
-	  Result = ejabberd_auth:check_password(User, Host, Pass),
+	  Result = ejabberd_auth:check_password(User, <<"">>, Host, Pass),
 	  gen_tcp:send(Socket,
 		       mod_proxy65_lib:make_auth_reply(Result)),
 	  case Result of
diff --git a/src/mod_register_web.erl b/src/mod_register_web.erl
index 5b7f950ad..d93140312 100644
--- a/src/mod_register_web.erl
+++ b/src/mod_register_web.erl
@@ -438,7 +438,7 @@ check_account_exists(Username, Host) ->
     end.
 
 check_password(Username, Host, Password) ->
-    case ejabberd_auth:check_password(Username, Host,
+    case ejabberd_auth:check_password(Username, <<"">>, Host,
 				      Password)
 	of
       true -> password_correct;