Thunking Spooler APIS from 32 to 64 process has stopped working

Hi
I have been reading alot of forums with lots of people having the same
problem as we are where when trying to print to a network printer with vista
64 bit edition the following error occurs "Thunking Spooler APIS from 32 to
64 process has stopped working". The only solution that seems to be given
everywhere is from the same person Alan Morris from the Windows Printing Team
where he asks if running Vista Sp1 and also points to the hotfix kb941962
which doesn't seem to solve anyones problems as that is normally where the
threads go dead after they reply that they have Sp1...
We have Sp1 and have tried the hotfix. We've also tried what everyone else
has tried which is reinstalling the network printers and drivers.
Details of error
Problem Event Name: APPCRASH
Application Name: splwow64.exe
Application Version: 6.0.6000.16386
Application Timestamp: 4549c865
Fault Module Name: x2rpclAP.dll
Fault Module Version: 5043.900.0.0
Fault Module Timestamp: 46e9498b

thanks for any help you can provide