Snow Leopard will not remember wireless connections

I have a 1.83 2CD Mac Mini, with a fresh install of Snow Leopard (although the problem still occurs if I use the original Leopard install disks). It will not remember wireless networks after a restart. I have tried:

1. Repairing permissions.

2. Fresh install.

3. Deleting Keychain and associated pref files.

4. Setting permissions in keychain.

Without any luck.

The hub is an Airport extreme, and the other macs on the network have no issues, (Lion and Snow Leopard).

Anyone have any ideas?

Is it possible to write an automator script to log it in after a restart?
Thanks!