Adje van den Berg was dutch pride in the early 80s. He released 3 album with his band "Vandenberg", before he joined Whitesnake.
In 2002 he was a guest musician on an album called "Attacks when provoked" (More (dutch) info: http://www.popinstituut.nl/index.htm?dat/index.htm?6435
It is hard to find some info about his current activities.
An dutch site in english language: http://www.euronet.nl/~wat/
The last thing I found on dutch website pages is that he now lives in the Netherlands and has a company who releases music (bad translation of "muziekuitgeverij").