--- a/trunk/src/wings_edge_loop.erl
+++ b/trunk/src/wings_edge_loop.erl
@@ -8,7 +8,7 @@
 %%  See the file "license.terms" for information on usage and redistribution
 %%  of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 %%
-%%     $Id: wings_edge_loop.erl 517 2009-03-11 19:37:10Z optigon $
+%%     $Id: wings_edge_loop.erl 599 2009-04-24 04:39:31Z bjorng $
 %%
 
 -module(wings_edge_loop).
@@ -186,7 +186,7 @@
 
 add_mirror_edges(Edges, We) ->
     MirrorEdges = gb_sets:from_list(mirror_edges(We)),
-    case gb_sets:is_empty(gb_sets:intersection(Edges, MirrorEdges)) of
+    case gb_sets:is_disjoint(Edges, MirrorEdges) of
 	true -> Edges;
 	false -> gb_sets:union(Edges, MirrorEdges)
     end.