[quote=priwjet1982]Don't trust your teachers, even if they are German. If you live abroad you forget stuff, trust me. It's perfect as Kamion said:
"wegen + dative case", "wegen mir, wegen dir,..."

In German you have the genitive, but it is almost extinct, a sentence with "wessen" is absolutely correct, e.g. "Wessen Auto ist das?"
But noone ever would say that, ok, people would laugh at you. A queen could say that if she was really posh and formal, but even then.
You usually use a dative case: "Wem geh