teamkilling with spells

I was just on and played as demo, set up some stickies and waited for the boss to come. My team mate use the exploding pumpkins spell and threw it right under me, set it off, and killed me by using it to detonate my stickies and it counted as me killing myself. Is there any way that the spell can be altered so something like that doesnt happen?

But stickies don't detonate unless you yourself press M2???

well apparently my stickies went off without me setting them off cause i know i didnt do it. They exploded right after a teamate used the pumpkin bomb spell and shot them right on top of me and my stickies. I guess i need to record a demo and post it.