ISPConfig stopped working after update

[wxman]

I ran aptitude update then aptitude safe-upgrade on a new server I'm building, and completely lost ISPConfig. I can't get Apache to start anymore either from the command line. When I try I get:

[error] VirtualHost *:80 -- mixing * ports and non-* ports with a NameVirtualHost address is not supported, proceeding with undefined results

I found one post here showing this error, http://www.howtoforge.com/forums/showthread.php?t=31803. Till's response is to edit the "apache default host file". Where is the apache default host file on an ISPConfig 3 install, and what needs to be changed?