In the MMC
Right-Click your server and select BlackBerry Server Properties

You can also check the version of BlackBerryAgent.exe or BlackBerryDispatcher.exe

To break down the version:
4.0.2.13=4.0.Service Pack 2.Hot Fix 3
Major.Minor.ServicePack.Bundle(Hotfix)

This Bundle/hotfix information is typically avail in the release notes.