I went to the datacenter,
did a complete new install of centos,
and ordered Direct Admin,
so I can't help you ...
But I will try it again next time with a different server,
this time I did not have enough time to resolve bugs.
It cost me a lot of time,
and although the installation guide at howtoforge and ISPconfig gives a complete manual on how to install on centos 5.2, there seems to be no support on bugs for this centos version (yet).
Too bad because I liked the look and feel of it ...