motor oils rated by API (American Petroleum Institute) will be signified as CF, CG, CH, etc. for diesel compression engines. The C = Compression Ignition as opposed to SG, SH, SJ designations, which refer to S (spark ignition). Some oils are rated for us in both diesel and gasoline engines, thereby having dual designations. The letters which follow the "C" or "S" relate to the age timeframe in which the oil was tested. A "CH" oil was tested and approved using a more stringent test than an older standard of "CF" or "CG".
API are of course american standards, which are prevalent on oil containers and literature. ACEA is a european association with designations such as B2, B3, B4, etc. These designations are rarely found, although I have seen them on the Amzoil website.
Checkout the following for MB recommendations and listing of some acceptable motor oils for MB 229.3 and 229.5:
www.whnet.com/4x4/oil.html