BBScreenshooter is a small tool that can be used to capture the current screenshot on Blackberry phones. It allows you to capture screens in multiple formats from your desktop windows desktop. You can preview screenshots before capturing.
To use BBScreenShooter, first you need to download JavaLoader tool and unzip it in a folder . Then download BBScreenShooter.exe file in same folder and run. Specify the location of Java Loader utility and application is ready to capture the screenshots of your Blackberry screen.
A detailed tutorial can be found HERE