this could be many problems and could potentionally be very expensive
it could be like what i have seen before i changed the door lock when this happend to a machine i was repairing and i later found out that the motor had blown so this could be your problem.
but like wise on anouther zanussi i had the same problem with the doorlock just clicking and it was only the heating element that had blown.
hope i have help you from my experience
good luck
Luke, May 2006