Lester,
I spent quite a lot of time trying to get the Apache/PG/OpenACS combo working, and it's apparently not compatible with the Apache/mod_ssl RPM's packaged with Mandrake 7.2, nor the Apache-ssl available elsewhere (which I used under RedHat).
It's a pain to have to learn AOLserver, which I find to be sluggish. Also, the memory leaks (presumably from TCL) or caching require daily restarts - at least on my system - to reclaim adequate RAM to prevent VM swapping. In short, I wish the Apache OpenACS had worked and was still being improved. As it stands now, I'm running both Apache and AOLserver, as well as both MySQL and PostgreSQL. Yuck!
PHPnuke (www.phpnuke.org) is gaining a lot of functionality that I found attractive in OpenACS. When it has personal home pages, I'll be ready to move off, and down, to just Apache and MySQL. Every part of this system will come in Mandrake - nothing to install.