The main remaining issue is the internationalization code. OpenACS also requires several additional modules that were not in the AOLserver source tree. These included nsoracle, nssha1, a working version of nspostgres, etc. For a long time, AOL was unresponsive to suggestions and patches, leading to a number of forked versions (OpenACS's isn't the only one) and causing much confusion for new users.
In the past few weeks, there's been a rather abrupt turnaround. Many of the modules scattered across the web have been incorporated into the AOLserver SF tree, often with patches that aren't in the OpenACS version. (The AOLserver nspostgres is still broken. Certain people here have been given the ability to import the fixed version but have been swamped with 4.6 and other work.) Nathan, Kriston, and Jim from AOL have been coming to the weekly AOLserver chats on AIM to get feedback from the community. So I'm optimistic about OpenACS being able to run on a stock AOLserver distribution sometime soon. I suggest joining the AOLserver mailing list and weekly chats if you haven't already.
