Have the same problem with my 98' C280. I replaced the (suspected to be) original battery shortly after I bought the car used and the problem has rarely occured (but has a couple of times). So, I'm not sure if it was the battery, or if the prob was caused by lack of use (starter-to-flywheel gear use/corosion etc as the car sat on a dealer's lot for more than 6 months before I bought it).