I was actually looking for a programmatic way to find it, but you helped a lot as I was able to find the version number with grep. The version I have will find it via:
grep 'server.*version' /home/admispconfig/ispconfig/lib/config.inc.php
Thanks for the help. The project I was working on had to take a hiatus for a few months, but I'm back on it again. Again, thanks for the response. I actually had looked in there, but as a reseller, not as admin (I rarely go in as admin).