OK: Here for 2008 where the Version is not displayed per default:
1. On the taskbar, click Start > Settings > Control Panel or Start > Control Panel.
2. Double-click Programs and Features.
3. If the window does not display the Version column, perform the following actions:
a. Right-click on any column heading. Click More....
b. In the dialog box, select Version.
c. Click OK.
4. In the list of currently installed programs, search for BlackBerry Enterprise Server
BES 5.0.1 MR1 = Bundle 70 (there has been a 72 - but it was recalled: See KB20277