If you get this error after upgrading from an older version of Password Safe (predecessor of OI Safe), install the older version again, export your passwords, deinstall and install the newer version, and import your passwords.
You can find old versions of Android Password Safe here:
http://code.google.com/p/android-passwordsafe/downloads/list?can=2&q=apk
Old versions of OI Safe are here:
http://code.google.com/p/openintents/downloads/list?can=1&q=oi+safe