I think there was a changeover from ODB I to ODB II in the late 90's up to the early 2000's.

Found some other information:
ODB I wiring of 38 pin plug (sorry, only found it in german language)
OBD-2 Techn.Info

Star Diagnisis System 2009 (sorry, only found it in german language) which includes several adapters.
eBay Österreich: Mercedes Star Diagnose MB Star 2009 DEUTSCH mit IBM T30 (Artikel 330350869765 endet 11.08.09 21:00:00 MESZ)

Regards

Markus