Enumerates email accounts through different methods like VRFY, EXPN and RCPT TO.
You will need argparse (http://code.google.com/p/argparse/) and dnspython (http://www.dnspython.org/), can be installed easily through pip (http://pypi.python.org/pypi/pip).
$ ./main.py -d acme.local -f accounts.txt -m all -o ./enumerated.txt