Thanks Rob and Chris for the replies. I will be nipping out in a few
minutes up to either Wicks or B+Q to see what they have in the way of
the two types of primer you suggest. Between writing the message and
getting a reply I tried lightly sanding an area on the rear of one of
the doors and wiping the dust off with a cloth containing white spirit.
I painted the prepped area with a vinyl silk emulsion but found that
the paint formed a rubberised skin in contact with the wood but after 4
hours had not really dried and simply wiping a finger across the
surface, just lifted the paint in sheet form. I just scraped the rest
of the paint off with a scraper. I will let you know the latest once I
get a proper primer.

Gio