http://bugzilla.openedhand.com/show_bug.cgi?id=1794
Index: matchbox-panel/mb-panel-scaling-image.c
===================================================================
--- matchbox-panel/mb-panel-scaling-image.c	(revision 2098)
+++ matchbox-panel/mb-panel-scaling-image.c	(working copy)
@@ -284,7 +285,7 @@
 
                 if (image->priv->caching) {
                         g_hash_table_insert (image->priv->cache,
-                                             image->priv->icon,
+                                             g_strdup(image->priv->icon),
                                              pixbuf);
                 } else
                         g_object_unref (pixbuf);