That's pretty lame. If you're talking to someone and they're annoying you and you don't want to carry on the conversation you have 3 options.
1) Turn your back and walk away
2) tell them to **** off they're a boring ****
3) Punch them in the face and knock their teeth out
Pick whichever one suits you best.
How did I not know about this??
There is a fake call thing on my fone but ive never used it lol