Aside, the currently available hddtemp package (0.3-beta15-33) of Ubuntu 7.04 is not capable of reading temperatures of SATA drives. I found that bug report, after fiddeling with the configuration files and init scripts.
Read how to do it at this blog
Maybe I could just have installed the binary Debian package or just wait for the Ubuntu package to be updated. But as Im new to the Debian world, having mainly used Red Hat style Linux until now, I see this as an exercise. Mixing apt repositories for Ubuntu with Debian ones is not recommended as far as I understand.