I posted this in another thread but I thought it might be worth calling this to everyone's attention:

I've been looking for a security app that permits encryption of important databases. I decided to use Teal Lock, since PDA Defense / Surewave doesn't appear to be a current product (can't buy it) and XForcer isn't compatible (they say they may update later...).

I should have realized encryption is a dicey proposition considering how often a Treo resets. Sure enough it reset mid-encryption and the databases were irretrievably corrupted. I restored from backup. Another time there seemed to be a subtler corruption, after a subsequent encrypt/decrypt, and DBScan couldn't fix it. I've lost a few days of Calendar and given up for now on encryption.

The only answer would seem to be a product that maintained the original file (unencrypted, or, during decryption, the encrypted file) until it verified that the encrypt/decrypt was complete. I don't think there is one at the moment but woiuld love to hear otherwise.