diff --git a/Lib/distutils/core.py b/Lib/distutils/core.py
index 13bf9c7fcbc..fd5ba907fb0 100644
--- a/Lib/distutils/core.py
+++ b/Lib/distutils/core.py
@@ -88,7 +88,7 @@ def setup (**attrs):
         ok = dist.parse_command_line (sys.argv[1:])
     except DistutilsArgError, msg:
         sys.stderr.write (usage + "\n")
-        raise SystemExit, msg
+        raise SystemExit, "error: %s" % msg
 
     # And finally, run all the commands found on the command line.
     if ok: