Chip/Jack,
For a better and more complete Apache vs AOLserver explanation, allow me to repost something Ben wrote that I think is a fantastic explanation. It comes from this thread (https://openacs.org/bboard/q-and-a-fetch-msg.tcl?msg_id=000545&topic_id=11&topic=OpenACS)
talli
AOLserver and Apache are not equivalent pieces of the application stack
Trying to replace AOLserver with Apache is like trying to replace Zope with Apache or WebLogic with IIS. They're two completely different things. You cannot replace AOLserver with Apache because they play completely different roles in the architecture. AOLserver is an application platform with a Tcl interpreter, a powerful database API, and a really fast threaded architecture. Apache is a web listener with a standardized API for adding different means of processing web requests.
If you want to compare AOLserver to something else, compare it to mod_perl. You might run Apache, mod_perl, and PostgreSQL as one architecture. You could also run Apache, mod_proxy-to- AOLserver, and PostgreSQL as another architecture. AOLserver is your *application server*. Now it just so happens that AOLserver is a darn good web listener, too. So you can take out the Apache layer and keep just AOLserver and PostgreSQL.
When Don says there's a solution in the works for Apache 2.0, what he means is that there is a mod_* solution in the works that will allow the easy layering of Apache 2.0 on top of AOLserver (or onto an AOLserver-like component that also does Tcl evaluation in a threaded environment with all the AOLserver APIs).
Now take a step back. If you have two architectures, one of which requires 2 components to function, the other one of which requires these same 2 components to function *plus* a third one.... which one presents less risk, increased simplicity, and generally a more sane platform?
AOLserver is not a web server. It is an application server. Layer all the web servers you want on top of it if it helps solve a marketing problem, but it will only make your technology platform that much more complicated.
