Welcome Jesse,
higher HTTP ports are not required if you use IP aliases (http://cr.yp.to/djbdns/ifconfig.html) combined with a HTTP proxy such as Pound (http://www.apsis.ch/pound/).
You are effectively running virtual servers behind a name based proxy. See http://www.thecodemill.biz/publications/blog/one-entry?entry%5fid=9968 and http://www.thecodemill.biz/publications/blog/one-entry?entry%5fid=9977 for more information on Pound and OpenACS.
/Bart
