Index: includes/parser/CoreParserFunctions.php
===================================================================
--- includes/parser/CoreParserFunctions.php	(revision 43935)
+++ includes/parser/CoreParserFunctions.php	(working copy)
@@ -58,8 +58,7 @@
 	static function intFunction( $parser, $part1 = '' /*, ... */ ) {
 		if ( strval( $part1 ) !== '' ) {
 			$args = array_slice( func_get_args(), 2 );
-			$message = wfMsgGetKey( $part1, true, false, false );
-			$message = wfMsgReplaceArgs( $message, $args );
+			$message = wfMsgExt( $part1, array( 'language' => $parser->getFunctionLang() ), $args );
 			$message = $parser->replaceVariables( $message ); // like $wgMessageCache->transform()
 			return $message;
 		} else {