oil leak

Hi folks,
Can anyone help me out with an oil leak on a 2002 TD6 vogue?
Ive got an oil leak and cant tell where its coming from. It has only started happening since i had it serviced and it leaks ever since.
The top half of the engine is very clean but the sump and all the surrounding area is covered in oil. It seems to be coming from both of the sump nuts but they are both tight. It has covered the transfer box and the crossmember but it is not obvious where its coming from. Ive had it all cleaned off, up on a ramp and left running for some time but it was dry as a bone. Typically it has started again, oil all over the garage floor and the bottom end of the engine. I am constantly dipping the oil but dont seem to be loosing any.
Any ideas please?
Many thanks,
Muffster.

Not wishing to state the obvious but I'd take it back to where you had it serviced, point out all the oil and ask them to rectify it. It sounds like they've re-used the sump plug washer or something equally silly and it's leaking out when the oil gets hot.

You're right mate! And i have done just that, the sump washer was completely deformed after the service but they re-used it! so i took it back and he sorted it out but it started leaking again after a while. They also over filled it. The garage is 30 miles away and now its just not an option to go over and use him again, and to be honest i dont want him touching the car again.
I have had another garage check it out since. He put another sump washer in, ran it for a while and couldnt see where it was coming from.
So, any offers where to look?
Cheers,
Muffster.

If the first garage over filled the engine sump with oil then they have most likely caused damage to the rear crankshaft oil seal

Ok mate, where is that exactly so i can have a look.
Cheers,
Muffster.