I have checked into svn the changes I have made to my ispconfig to install TYPO3 automaticly.
It contains of 2 changes to the database, an extra field to isp_server that holds the directory for the TYPO3 sources, and a table isp_isp_web_package that holds the data that is sent from the web part of ispconfig to the root scripts.
I have added a TYPO3 dir and some files to /home/admispconfig/ispconfig/web/tools/tools/ and a template file to /home/admispconfig/ispconfig/web/templates/
In the /root/ispconfig/scripts/ dir i have added a few lines to writeconf.php and a function to lib/config.lib.php to make the actual TYPO3 install.
The source files and TYPO3 db dump that I use are available for download from http://www.mit-inter.net/index.php?id=19
you just unpack it from the root so the files are placed in /usr/share/TYPO3/.
I have a lot of experience programming with php, mysql etc, but not with ISPconfig, so feel free to come with improvement suggestions.