So I go to start my car and the key won't move out of the position I put it in. The problem started around wednesday, but I managed to move the streering wheel back and fourth and it let the key start the engine.

So I called mercedes roadside assistance and they say that there's nothing they can do, but call a tow truck driver. The mercedes tech said maybe one of the keys in the ignition lock wore down or something to that nature. I know it's not the key, because it works in the door and I even tried that master key.
I read thisTHREAD on the forum, but he did not state the resolution. Does anyone know any thing about this problem, what I can do about it, and what might it cost. Oh, and the tow truck guy is going to charge me $100 to tow it down the road. Oh well. The car is a 96 c220 with almost 140000 miles. Any help would be appreciated.