After spending a lot of time painfully configuring mongrel + mod_proxy + apache + … there now is an official release of mod_rails aka passenger which works pretty well :)
The installer wasn't really that great (had to download the source and use the bundled installer because some ansi problems I think) and I had to copy a bunch of files to get the things where they should be, but now it works (as you can see).
According to the benchmarks it should be fast :)
Hm, seems as if the module needs a little bit more dev-time :)
[Sun Apr 13 11:03:48 2008] [error] [client XX.XX.XX.XX] * Unexpected error in Passenger: write() failed: Broken pipe (32)