I'm posting this in the event it can be useful to someone else:
After upgrading to the latest 12.10 release, MythWeb started showing a blank page. Not finding anything on the ubuntuforums I poked around and found this:
If you have the following error appearing in your /var/log/apache2/error.log:
Applying the patches provided in that but thread resolved the PHP Fatal error so that MythWeb now works again.
[Sun Oct 21 10:08:24 2012] [error] [client 192.168.1.26] PHP Warning: Unknown: function '0' not found or invalid function name in Unknown on line 0
[Sun Oct 21 10:08:25 2012] [error] [client 192.168.1.26] PHP Fatal error: Call-time pass-by-reference has been removed in /usr/share/mythtv/bindings/php/MythBase.php on line 50