Index: includes/parser/Parser.php
===================================================================
--- includes/parser/Parser.php	(revision 46632)
+++ includes/parser/Parser.php	(working copy)
@@ -3731,6 +3731,11 @@
 			'~~~~' => "$sigText $d",
 			'~~~' => $sigText
 		) );
+		
+		# Username pseudo-magic word
+		$text = strtr( $text, array(
+			'__USERNAME__' => $user->getName(),
+		) );
 
 		# Context links: [[|name]] and [[name (context)|]]
 		#