diff --git a/src/gen_mod.erl b/src/gen_mod.erl
index 4dc972fd9..6804d4785 100644
--- a/src/gen_mod.erl
+++ b/src/gen_mod.erl
@@ -44,7 +44,7 @@
 %% Deprecated functions
 -export([get_opt/3, get_opt/4, get_module_opt/4, get_module_opt/5,
 	 get_opt_host/3, get_opt_hosts/3, db_type/2, db_type/3,
-	 ram_db_type/2, ram_db_type/3]).
+	 ram_db_type/2, ram_db_type/3, update_module_opts/3]).
 -deprecated([{get_opt, 3},
 	     {get_opt, 4},
 	     {get_opt_host, 3},
@@ -305,6 +305,19 @@ store_options(Host, Module, Opts, Order) ->
 	       #ejabberd_module{module_host = {Module, Host},
 				opts = Opts, order = Order}).
 
+-spec update_module_opts(binary(), module(), opts()) -> ok | {ok, pid()} | error.
+update_module_opts(Host, Module, NewValues) ->
+    case ets:lookup(ejabberd_modules, {Module, Host}) of
+	#ejabberd_module{opts = Opts, order = Order} ->
+	    NewOpts = lists:foldl(
+		fun({K, _} = KV, Acc) ->
+		    lists:keystore(K, 1, Acc, KV)
+		end, Opts, NewValues),
+	    reload_module(Host, Module, NewOpts, Opts, Order);
+	_ ->
+	    error
+    end.
+
 maybe_halt_ejabberd() ->
     case is_app_running(ejabberd) of
 	false ->
diff --git a/test/offline_tests.erl b/test/offline_tests.erl
index fbf1fbf74..d86cc36b9 100644
--- a/test/offline_tests.erl
+++ b/test/offline_tests.erl
@@ -144,7 +144,8 @@ unsupported_iq(Config) ->
 master_slave_cases() ->
     {offline_master_slave, [sequence],
      [master_slave_test(flex),
-      master_slave_test(send_all)]}.
+      master_slave_test(send_all),
+      master_slave_test(from_mam)]}.
 
 flex_master(Config) ->
     send_messages(Config, 5),
@@ -174,6 +175,17 @@ flex_slave(Config) ->
     0 = get_number(Config),
     clean(disconnect(Config)).
 
+offline_from_mam_master(Config) ->
+    Server = ?config(server, Config),
+    gen_mod:update_module_opts(Server, mod_offline, [{use_mam_for_storage, true}]),
+    send_all_master(Config),
+    gen_mod:update_module_opts(Server, mod_offline, [{use_mam_for_storage, false}]),
+    wait_for_slave(Config).
+
+offline_from_mam_slave(Config) ->
+    send_all_slave(Config),
+    wait_for_master(Config).
+
 send_all_master(Config) ->
     wait_for_slave(Config),
     Peer = ?config(peer, Config),
@@ -298,7 +310,7 @@ get_nodes(Config) ->
     MyBareJID = jid:remove_resource(MyJID),
     Peer = ?config(peer, Config),
     Peer_s = jid:encode(Peer),
-    ct:comment("Getting headers"), 
+    ct:comment("Getting headers"),
     #iq{type = result,
 	sub_els = [#disco_items{
 		      node = ?NS_FLEX_OFFLINE,