This is old information, too, but I hope it is still useful. When I was attempting to install the most recent version of Blackfish (successor to JDataStore) on my Macbook Pro with Leopard, the install failed. Looking in the console for a clue as to what went wrong, I discovered:

08/08/03 12:03:02 PM [0x0-0x30b30b].jds_install[50294] sh: /usr/sbin/lookupd: No such file or directory

This is not an uncommon problem for Leopard. The lookupd command was replaced by dscacheutil. I got around the problem, and got the install to complete successfully by doing this from a terminal:

lori@draco ~
$ cd /usr/sbin
lori@draco /usr/sbin
$ sudo ln -s /usr/bin/dscacheutil lookupd

Make sure you delete that lookupd link when you are finished. The syntax for dscacheutil is similar, but not identical, and you might end up with other weird errors if you forget, and some application tries to use lookupd in a different way.