--- a/mercurial/simplemerge.py	Wed Aug 24 05:42:41 2011 -0400
+++ b/mercurial/simplemerge.py	Thu Aug 25 20:21:04 2011 -0400
@@ -445,7 +445,7 @@
         out.write(line)
 
     if not opts.get('print'):
-        out.rename()
+        out.close()
 
     if m3.conflicts:
         if not opts.get('quiet'):