I eventually got jack with pd running on my Debian machine. the Jack package installs libjack version 100. I just made a symbolic link in my /usr/lib directory with the command
ln -s libjack-0.100.0.so.0.0.23 libjack-0.80.0.so.0 (your specific version may be different)
Do you think this was a bad idea? I don't remember whose idea it was first... I'll take the blame if it messes up. Otherwise, someone else gets the credit :)
Chuck