Whoa guys. Don't scare him to death!
I have an 89 190E 2.0 that uses a whole schwack of oil. I freaked when I first got it, but then I looked in the owners manual. Depending on how much the engine is stressed (and in hilly Pennsylvania, the poor little 2.0 is VERY stressed), "normal" oil consumption can be up to 1.5 liters per 1000km. My car uses about a quart per 600 miles, so I'm well within "normal". Even though I use so much oil, the car doesn't smoke. This is not to say that oil consumption is *desirable*... but it is, according to my owner's manual, acceptable.