If you try installing the BlackBerry JDE Plug-in for Eclipse using the BlackBerry update site you will probably receive the following error:

An error occurred while collecting items to be installed Error closing the output stream for net.rim.EclipseJDE/org.eclipse.update.feature/1.0.0.67 on repository file:/C:/eclipse-SDK-3.4.1-win32/eclipse/. Error unzipping C:\DOCUME~1\scottt\LOCALS~1\Temp\net.rim.EclipseJDE_1.0.0.674162146521096327961.jar: Invalid zip file format Problems ...

There is a post on the BlackBerry support forum which says that the issue is related to their update site and that you need to download the plug-in:

http://na.blackberry.com/eng/developers/javaappdev/javaeclipseplug.jsp

It is also important to make sure that you have a valid version of Eclipse.  You need Ganymede 3.4 or 3.4.1.  You can download it here.  

I didn’t have much luck with the Full Installer.  I downloaded one of the component packs instead and manually added the packages to Eclipse.  When I ran the full installer the video display on my computer froze.

Go to Windows/Preferences once you have copied the correct files to the features and plugins folders in Eclipse.

Troy