Many moons ago an official RIM list of BES version numbers was pointed out for all mail server platforms. Below are the links for each platform:
BES 4.0 & 4.1 for Microsoft Exchange
BES for IBM Lotus Domino
BES for Novell GroupWise
So what you can do is check your BES version number against the list that applies to you and you'll know if you need to install any updates!!!
Check your BES version number
1) Go to the Add or Remove Programs Control Panel applet (Start > Run > appwiz.cpl )
2) Locate the reference to "BlackBerry Enterprise Server", select it and then click "Click here for support information.".
3) The publisher listed should be "Research In Motion" and the Version will be the exact version of BES currently installed.