okay, i'm a little confused. i see what you're referring to, but i'm lost on the apache2.conf thing. ours is SLES10, and we have httpd.conf in /etc/apache2. is apache2.conf in your system the same as httpd.conf in ours?
as for that ispconfig-created SSL entry stuff, when i click the enable SSL checkbox under ispconfig, it does NOT create an entry like that in vhosts. i'm not sure what it *does* do, but what you show is definitely not it.
i can add in manually the SSL stuff that you show, if that will work. that still doesn't help me identify where apache is loading any other SSL or RSA information. in order to make SSL work with a given virtual host, i need that "SSLEnable On" statement in the vhost definition. if i enter that statement, i get the "Multiple RSA server certificates not allowed" error. for me, i think the first order of business is to identify what's causing that if possible. any suggestions?