[SOLVED] Dreaded Error 500 on my 20th domain only

[ShinZan]

Im really putting some mileage on this forum

So Ive migrated my old 1.00 box to 1.07 and everything is plunking along just fine but now i added a new domain to my box and any type of .php processing gives error 500. The log files don't say anything helpful or perhaps im just looking at the wrong log files. I'm looking at var/log/apache2 logs and see nothing useful.

Im on Ubuntu 10.1
ISPCP 1.07

the index.html processes fine but the index.php of the 2.5 joomla just gives error 500. I tried removing the domain and readding it giving it a new virtual user group id but that didn't help, I rebooted the server wondering if something might be out of memory too in desperation but that wasn't it either.

Can anyone point me toward what I need to do to troubleshoot this? I assume all new domains will also have this problem too.

Thanks!

David