diff --git a/ChangeLog b/ChangeLog
index d8bb35775..c9a7a1db0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2009-02-13 Christophe Romain <christophe.romain@process-one.net>
+
+	* src/ejabberd_auth.erl: prevent from calling 
+	get_vh_registered_users/2 when not available
+
 2009-02-06  Jean-Sébastien Pédron  <js.pedron@meetic-corp.com>
 
 	* src/web/ejabberd_web.erl, src/web/ejabberd_http.erl: Add
diff --git a/src/ejabberd_auth.erl b/src/ejabberd_auth.erl
index 6156b13bc..8e267ec37 100644
--- a/src/ejabberd_auth.erl
+++ b/src/ejabberd_auth.erl
@@ -242,7 +242,13 @@ get_vh_registered_users(Server) when is_list(Server) ->
 get_vh_registered_users(Server, Opts) when is_list(Server) ->
     lists:flatmap(
       fun(M) ->
-	      M:get_vh_registered_users(Server, Opts)
+		case erlang:function_exported(
+		       M, get_vh_registered_users_number, 2) of
+		    true ->
+			M:get_vh_registered_users_number(Server, Opts);
+		    false ->
+			M:get_vh_registered_users_number(Server)
+		end
       end, auth_modules(Server)).
 
 %% @spec (Server) -> Users_Number