John- I replaced all of the light bulbs(OSRAM) on the rear of the car. The cruise control now works! Thanks. It was intesting to note that all of the old bulbs looked rather fried......though they all still worked. All of the elements on the inside of the bulbs looked corroded.
I sure appreciate your "quick fix".

I do have another question. Though the cruise now works, and stays on when engaged, it does seem a little bit hesitant when first turned on. Is this a symptom of another ailment or is this how MB cruise controls work? I guess what I'm talking about would be best described as a slight lag when you first engage the CC.