Nicholas Petreley writes The Open Source column
in Infoworld.  This week's column (Apr 30,'01) is titled:
Running the gamut of Web publishing systems, application 
languages, and tools
Here is the relevant part:
The other alternatives readers mentioned include ArsDigita 
(www.arsdigita.com) and the OpenACS Open ArsDigita Community System 
for Web publishing (openacs.org). Both of these are based on the TCL 
scripting language, although ArsDigita also uses Java. Both are based 
on the America Online Web server (www.aolserver.com). By the way, the 
AOL Web server is a truly nifty and vastly under-rated open-source 
Web server. I'm surprised it doesn't get more attention from the open-
source community. 
Anyway, ArsDigita uses Oracle for its database. OpenACS uses the 
open-source database PostgreSQL. I'm having a terrible time getting 
OpenACS running. I recommend the Getting Started tutorial article at 
the Developer
 Shed (www.devshed.com/Server_Side/PostgreSQL/OpenACS). The 
article omits a lot of information for anyone using a Linux 
distribution other than the author's, but it's still the best bet I 
know of for getting OpenACS to work.
-Bob