--- a/mercurial/merge.py	Wed Mar 19 23:04:03 2014 -0700
+++ b/mercurial/merge.py	Tue Apr 01 15:11:19 2014 -0500
@@ -78,8 +78,8 @@
                 bits = record.split("\0")
                 self._state[bits[0]] = bits[1:]
             elif not rtype.islower():
-                raise util.Abort(_('unsupported merge state record:'
-                                   % rtype))
+                raise util.Abort(_('unsupported merge state record: %s')
+                                   % rtype)
         self._dirty = False
 
     def _readrecords(self):