How allow users to install their own plugins...

I am not sure if this works in a fresh install of WPMU or not, but I would like users to be able to install/add their own plugins.

I am using the 'support' and 'plugin manager for support' plugins from WPMUDEV.ORG and they work great for allowing / disallowing certain plugins for 'supporters'.

I am not sure if these plugins have modified the 'add plugin' menu for users or not, but I would like it back. Is there any way to force ths menu option to appear in the users' admin?

Any insight, hack, or workaround is greatly appreciated!