Use namespace definitions when possible

src/mod_admin_extra.erl

@@ -1068,7 +1068,7 @@ subscribe(LU, LS, User, Server, Nick, Group, Subscription, _Xattrs) ->
     mod_roster:set_items(
 	LU, LS,
 	{xmlel, <<"query">>,
-            [{<<"xmlns">>, <<"jabber:iq:roster">>}],
+            [{<<"xmlns">>, ?NS_ROSTER}],
             [ItemEl]}).
 
 delete_rosteritem(LocalUser, LocalServer, User, Server) ->
@@ -1085,7 +1085,7 @@ unsubscribe(LU, LS, User, Server) ->
     mod_roster:set_items(
 	LU, LS,
 	{xmlel, <<"query">>,
-            [{<<"xmlns">>, <<"jabber:iq:roster">>}],
+            [{<<"xmlns">>, ?NS_ROSTER}],
             [ItemEl]}).
 
 %% -----------------------------
@@ -1250,7 +1250,7 @@ private_get(Username, Host, Element, Ns) ->
 	   [{xmlel, Element, [{<<"xmlns">>, Ns}], []}]}},
     ResIq = mod_private:process_sm_iq(From, To, IQ),
     [{xmlel, <<"query">>,
-      [{<<"xmlns">>, <<"jabber:iq:private">>}],
+      [{<<"xmlns">>, ?NS_PRIVATE}],
       [SubEl]}] = ResIq#iq.sub_el,
     binary_to_list(xml:element_to_binary(SubEl)).
 

src/mod_configure.erl

@@ -2022,14 +2022,14 @@ stop_node(From, Host, ENode, Action, XData) ->
 				       #xmlel{name = <<"x">>,
 					      attrs =
 						  [{<<"xmlns">>,
-						    <<"jabber:x:data">>},
+						    ?NS_XDATA},
 						   {<<"type">>, <<"submit">>}],
 					      children = SubEls},
 				   others =
 				       [#xmlel{name = <<"x">>,
 					       attrs =
 						   [{<<"xmlns">>,
-						     <<"jabber:x:data">>},
+						     ?NS_XDATA},
 						    {<<"type">>, <<"submit">>}],
 					       children = SubEls}]},
 	  To = jlib:make_jid(<<"">>, Host, <<"">>),

src/mod_register.erl

@@ -282,7 +282,7 @@ process_iq(From, To,
 				 [#xmlel{name = <<"query">>,
 					 attrs =
 					     [{<<"xmlns">>,
-					       <<"jabber:iq:register">>}],
+					       ?NS_REGISTER}],
 					 children =
 					     [TopInstrEl | CaptchaEls]}]};
 		   {error, limit} ->
@@ -304,7 +304,7 @@ process_iq(From, To,
 			   [#xmlel{name = <<"query">>,
 				   attrs =
 				       [{<<"xmlns">>,
-					 <<"jabber:iq:register">>}],
+					 ?NS_REGISTER}],
 				   children =
 				       [#xmlel{name = <<"instructions">>,
 					       attrs = [],