Index: navit/gui/internal/gui_internal.c
===================================================================
--- navit/gui/internal/gui_internal.c	(revision 4643)
+++ navit/gui/internal/gui_internal.c	(working copy)
@@ -2256,7 +2256,40 @@
 removecase(char *s) 
 {
 	char *r;
+#if HAVE_GLIB
+	gchar *p1,*p2,*pp;	
+	r=g_utf8_normalize(s,-1,G_NORMALIZE_ALL);
+	if(!r) {
+		pp=g_strdup(s);
+		if(!g_utf8_validate(pp,-1,&p1)) {
+			if(p1) {
+				dbg(0,"Invalid utf8 string %s will be cut at byte pos %d\n", p1-pp);
+				*p1=0;
+				r=g_utf8_normalize(s,-1,G_NORMALIZE_ALL);
+			}
+			if(!r) {
+				dbg(0,"Unable to fix broken utf8 string %s\n",s);
+				r=g_strdup("");
+			}
+		}
+		g_free(pp);
+	}
+	for(p1=r,p2=r;*p1;) {
+		gunichar c=g_utf8_get_char(p1);
+		pp=g_utf8_next_char(p1);
+		if(!g_unichar_iszerowidth(c)) {
+			memmove(p2,p1,pp-p1);
+			p2+=pp-p1;
+		}
+		p1=pp;
+	}
+	*p2=0;
+	pp=g_utf8_casefold(r,-1);
+	g_free(r);
+	r=pp;
+#else
 	r=g_utf8_casefold(s,-1);
+#endif
 	return r;
 }