Good suggestion, I recall that in some way or another, there was a way to detect it in scripting. Im not all to sure though but I could have swore ive done it before. Try using and if and see if BOTH right and left mouse buttons are done, I believe that if the middle mouse button is pushed, it triggers both left/right buttons to be down. Im not all to sure, its worth a shot...I'd test it, but im at work at the moment, damnot firewalls...

If it doesnt work let me know, i'll make a dll