Enhanced Logging to access.log?

[BlackRook]

Is there a solid mod out there that does enhanced logging to access.log or to a custom log?

What I need to do is log all user log-ins on authentication, along with IP, to the log. We need this for enhanced security on our private board. This is not a public board, before anyone raises concerns about privacy and so on.

I am sure that this is a one-liner mod to a single file or two, but would like some feedback on if this is already out in the wild, considerations and caveats, and so on.

Any help, pointers to file/methods, accepted and appreciated.

--------------- Added [DATE]1347632881[/DATE] at [TIME]1347632881[/TIME] ---------------

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