Summery: My SMS app crashes on OS 4.0 with an sms.db from 3.0

I have an iPhone 3G which had OS 3.0. I recently installed 4.0 (pwnage tool 4.1). I did not want to restore the data since I wanted a clean install and most of my data is synced anyway with gmail and such. The only thing that was missing is the sms.db

I extracted the sms.db from a backup of my 3.0 system (using iPhone Backup Extractor app), and copied it to the new 4.0 system. Opening the SMS app I saw all of my texts and was very happy. Until I tried to send a text which caused the app to crash. I then noticed that deleting texts and quitting the app doesn't really delete them. When I reopen the SMS app they're still there.
It's as if the app can't write to the DB properly.

I checked permissions and they seem to match the original sms.db that was on the 4.0 system.

I also used an SQLite editor to make the 3.0 db as similar to the new 4.0 db but no luck.

Has anyone managed to hack this thing??