Another Blue smoke problem!

I have a 300tdi which had a new head gasket and head skim fitted about a month ago. Its covered about 600miles after the repair and is now pumping out blue smoke when i put the pedal down rapidly and when its under pressure/
The temp is fine and the repairs were done by a Landy dealerdship in Belgium. so it's not as thou i can take it back to the garage with ease
There's a slight liquid seapage from around no4 cylinder. Any Ideas as to problem would be appreciated.
I want to attempt the repairs myself but need an idea before taking the head off.
Thanks in advance

it could be the turbo... check the inside of the inlet pipes for traces of engine oil

blue smoke is engine oil burning, if enough of this oil is finds it's way into the cylinders, you run the risk of the engine running on it's own oil and not being able to shut the engine off and it will just keep running faster and faster 'till it goes bang... I watched my mates 200 do this the other day!

Thanks Battenberg for this, i have taken a quick look at the inlet manifold removing the top hose from the intercooler and noticed heavy black oil on the inside also the link between the exhaust manifold and the down pipe the is oil seepage coming from the gasket joint.
I assume that this means the oil seals on the Turbo have gone and i need to get a replacement turbo?
Thanks