Thanks mate, now though I'm getting a windows message 'distributed client.net has stopped working' as soon as it starts. I'll have a play, see if I can figure it out.
... I still can't get it to work on the 7970 machine, but I tried it on the 2 x 7950s machine and got over 4 billion keys/sec on stock and over 5 billion OC'ed but my cards didn't like the CPU running, even a couple of cores killed my output, so I'll give it a go some other time, I need the CPU cores ATM.
... I updated the ATi drivers on the 7970 it's now working

getting over 3 billion keys/sec on it.