Why are you coming to us for this? You can just block anyone who adds you to a call and be done with it.
this is exactly what i was going to say. i've had stupid handicaps do this stuff all the time until i blocked and removed them from skype. that's all it takes. chances are if they're the kind of losers who do this stuff frequently they're not good company to even keep on your contacts list.
there's no reason to come to the forum about it. they're just going to stuffpost in this thread about how you're butthurt or something and make you angry.
can you get called by people who aren't in your contacts list?
you can if you want i believe, it's a selectable setting.