Jack, one solution is to just call AOLserver the "application layer" and use Apache as the web server. AOLserver is basically a souped up, kick ass version of Apache + mod_xxx with a whole bunch more.
A lot of these orgs would have no problem using Apache + BEA Weblogic/Jakarta/Websphere + Oracle. Saying that your app is Apache+AOLserver+Oracle might solve your server marketing issue.
To replace AOLserver entirely with Apache+mod_nsd is a massive effort, and one potentially worth doing. But it will probably be via an open source community and require a lot peer review and bug testing. I fear it wouldn't be that much different from just porting the code to Java.
Of course, as always, I could be wrong on that last point.
talli
