I doubt you'll find much interest with those of us doing most of the OpenACS port work. Apacheweek.com just posted a link to an article benchmarking Apache and AOLserver for (apparently) returning static pages, which showed AOLserver serving up pages at about three times the rate that Apache does (and 10 times the rate that Zope does). Thanks for the pointer to that, Dan!
While I'm always skeptical of benchmarks, the reality is we know that AOLserver is an extremely efficient webserver. I have no reason to switch to Apache, or to put energy into making OpenACS work with Apache. ArsDigita has business reasons for wanting ACS Classic to work with Apache, but we OpenACS folks aren't a business.
So, feel free to make it work with mod_aolserver if you want (I think you'll need to rewrite the Postgres database driver, but I'm not 100% certain of that). But if you're only doing so because you know Apache 's popular, and don't have a better reason than that, you're wasting your time.
Now, one thing Apache does is handle virtual servers. Progress on repairing this breakage in AOLserver 3.0 has been happening, though, and AOLsever 2.* handled virtual servers just fine and copies of the binaries can be found if you look hard enough.