Index: libnautilus-private/nautilus-directory-async.c
===================================================================
--- libnautilus-private/nautilus-directory-async.c	(revision 14096)
+++ libnautilus-private/nautilus-directory-async.c	(working copy)
@@ -844,7 +844,8 @@ dequeue_pending_idle_callback (gpointer 
 
 			/* Add the MIME type to the set. */
 			if ((file_info->valid_fields & GNOME_VFS_FILE_INFO_FIELDS_MIME_TYPE) != 0
-			    && directory->details->load_mime_list_hash != NULL) {
+			    && directory->details->load_mime_list_hash != NULL
+			    && file_info->mime_type != NULL) {
 				istr_set_insert (directory->details->load_mime_list_hash,
 						 file_info->mime_type);
 			}
