@@ -277,6 +277,8 @@ def make_command(prog, flags="", overwrite=False, quiet=False, verbose=False,
raise ScriptError("'-' is not a valid flag")
args.append("-%s" % flags)
for opt, val in options.iteritems():
+ if opt in _popen_args:
+ continue
if val != None:
if opt.startswith('_'):
opt = opt[1:]