kwargs not processed correctly. getting back entire dict of kwargs for a single kwarg's value

mymodule.py

#Salt module mymodule.py:
import logging
log = logging.getLogger()
def do_something(foo=None):
    log.debug('FOO? {0}'.format(foo))

output.log

[DEBUG   ] Command details {'tgt_type': 'glob', 'jid': '20131217213543992204', 'tgt': '*', 'ret': '', 'user': 'sudo_cari', 'arg': [{'foo': 'bar', '__kwarg__': True}], 'fun': 'mymodule.do_something'}
[DEBUG   ] FOO? {'foo': 'bar', '__kwarg__': True}

runme.py

# Code run from master
from salt.client import LocalClient
client = LocalClient()
kwargs = {'foo':'bar'}
client.cmd('*', 'mymodule.do_something', (), kwarg=kwargs)