From http://dotnetjunkies.com/WebLog/sriram/archive/2005/02/23/56452.aspx :
"I was talking to a former MSFT employee who worked on the CLR team. The
conversation drifted towards languages used to implement virtual
machines. Here's what I learnt.
The CLR's Garbage Collection was initially written in Lisp by a Patrick
Dussud [...]. This code was then run through a Lisp->C converter which
was then cleaned up by an intern."
CLR = Common Language Runtime = .NET's virtual machine
Pascal