As it's from Jersey, it's probably never got hot in it's life. The oil emulsifies in the rocker box. I suggest you buy a new gasket, remove the rocker cover, give it a thorough clean and replace it. Then run the car till the engine's really hot, drain the oil, refill with flushing oil and give the car a gentle run to clean it out. Next, drain the flushing oil, renew the filter and refill the sump with a good quality oil. If your normal usage of the car gets it up to working temperature, then you should have no further problems.
PS Clean the breathers out, too.
Pete
August 2007