--- a/misc_gui.c	Sat Dec 30 00:46:48 2006 +0000
+++ b/misc_gui.c	Sat Dec 30 01:08:12 2006 +0000
@@ -1226,7 +1226,10 @@
 			break;
 
 		case WE_DESTROY: /* Call callback function (if any) on window close if not yet called */
-			if (!q->calledback && q->proc != NULL) q->proc(w->parent, false);
+			if (!q->calledback && q->proc != NULL) {
+				q->calledback = true;
+				q->proc(w->parent, false);
+			}
 			break;
 	}
 }