fix bug introduced in b13a98bd078e

mercurial/commands.py

@@ -3308,7 +3308,7 b' def dispatch(args):'
         except (util.SignalInterrupt, KeyboardInterrupt):
             raise
         except Exception, inst:
-            u.warn(_("*** failed to import extension %s: %s\n") % (x[0], inst))
+            u.warn(_("*** failed to import extension %s: %s\n") % (ext_name, inst))
             if u.print_exc():
                 return 1