trigger exception in generator

[Dominic]

I would like to trigger an
exception in a generator
upon return from "yield"
e.g.

def mySimulationTask():
   while 1:
      try:
         # drive forward one simulation step	
         yield
         # do some stuff
      except HitWall:
         # handle this disaster ;-)

How can I possibly do this?
Maybe by hacking some internal
generator variables? ;-)

Thanks,
  Dominic

h i l l b r _at_ rhrk.uni-kl.de