Even though it is possible to deploy the PGP Support Package Over The Air (OTA) via the BlackBerry Enterprise Server (BES), after configuring the package on the BES, you may encounter an error:
The application net.rim.blackberry.secureemail.pgp version Unknown is missing.
This is a known issue where the BlackBerry Administration Service could not resolve dependencies on a SMIME_lib specified in BlackBerry.alx. This issue also affects the PGP Support Package for BlackBerry. This is outlined in a KB article on the RIM site: