Here's how I have the catalog details setup..

Catalog Name: maemo Extras ~ chinook
Web Address: http://repository.maemo.org/extras/
Distributions: chinook
Components: free non-free

Catalog Name: maemo Extras ~ diablo
Web Address: http://repository.maemo.org/extras/
Distributions:
Components: free non-free

However both will refuse to refresh.

Jeez when things go bad they really go bad. (I'm trying to reinstall apps on my internal flash memory so next time my SD card corrupts I won't have to reinstall everything when I clone it... if I get the bloody SD card partitions fixed.