--- gui/gdmcommon.c.orig	2007-07-17 09:59:20.000000000 +0200
+++ gui/gdmcommon.c	2007-07-17 09:59:54.000000000 +0200
@@ -399,7 +399,7 @@ gdm_common_text_to_escaped_utf8 (const c
 	while ((*p != '\0') && 
 	       !g_utf8_validate (p, -1, &q)) {
 		p = (gchar *) q;
-		p = '?';
+		*p = '?';
 		p++;
 	}