Making a module re-enter the stack

[Joe Lewis]

Hello, all;

I was curious.  Is it possible to create a module that can re-enter the
stack of modules?  Here's what I am interested in creating.

I constantly get a copy of security logs mailed to me, and they consist of
one particular individual who has different usernames with different
companies.  I'd like to create a module that will scan an "aliases" file,
and check the username and it's aliases against the current service's
configuration.

It's easy enough to build something that can grab a list of aliases from a
file, but I'm not sure if its even possible to force PAM to try again with
a "different" username.  I know it's also easy enough not to enter an
endless loop by using a flag - "I have been here".

Ideas?

Joe Lewis