Show separate dot icons for buddies on forumdisplay

Hi all,

Currently, a dot icon can be shown to identify the threads that I started or participated in. I have a real need to expand this to show a separate icon to identify those threads that my buddies have started or participated in. This icon can be displayed alongside my own dot icon if a buddy and myself both participated in the same thread.

I have tried (unsuccessfully) to hack forumdisplay.php. Could anyone give me some guidance on how to go about this?

Many thanks,

Willie