I know you said you don't want to restore it, but I will suggest that anyway. Assuming it hasn't been completely disabled you should be able to do a backup and sync with the computer you have synced it with before, but not a new computer. Then you can easily restore all your app and other data. It won't help restore your jailbreak stuff though.
I ran into this same problem a couple weeks ago and wasn't able to find a better answer. I am sure it must be possible, especially if you have ssh enabled. I did see a post on this forum suggesting a method to bypass the lock through ssh. You may find it in a search.
