Progress Custom Alerts and UserID's

[system]

I'm setting up some custom .p file for BAM alerts in Vntg 6.0. One of
the alerts monitors changes to vendor terms. The alert works, we can
send the vendor's name and what got changed but we'd like to add the
UserID of who made the change.

Any idea what table I need to pull in and how to do it?

Thanks!

- Erik