[mjcole2003]

im guessing that you did not do a nandroid back up of your earlier rom with the working 4g. Ive read that its better to use the amon ra recovery as oppossed to clockwork mod recovery being that amon ra also backs up the wimax rsa encryption keys and cw mod does not.

edit:i just read that nandroid backups(made in RA,at least) are backwards compatible. So if you made a backup on 1 .8.0 ,then upgraded to 2.2.1, the backups would still work unless you upgraded your hboot version since that backup was done.

edit,edit: I found a cool app on the market called Wimax Keys Checker that checks to see if your key's are intact...must be rooted : )