Of course, it can’t; two solutions for two very different problems. OpenID is targeting authentication while a password manager like PassPack is trying to make storage of passwords as secure as possible. However the PassPack folks are thinking about implementing OpenID for signing in to PassPack.
If you are already using PassPack and would like to see it supporting OpenID leave a comment on their blog. PassPack has some strong security features like SSL connections, AES encryption, and also anti-phishing solutions already, so signing in with an OpenID will be very secure.
For more information on PassPack see previous coverage on this blog.