Scanning With Credentials Using Nessus 4.2

[MuhammadVonRaven]

I read a 2009 blog entry titled, 'Protecting Scanning Credentials from Malicious Insiders.'

I'm pen-testing my lab in which my host machine is running the Nessus credential scan against a *nix and a XP image on VMware. On the *nix image, I'm trying to use Metasploit to capture the credentials of the XP image.

Any ideas on how to do this?