PVA on my wall from builder

So we've had a window put in our wall and the plasterer got a bit enthusiastic with the PVA before he made the opening good.

So basically, we are about to decorate and have mainly old paint, some new plaster and some old paint, which has been PVA'd over.

What do people advise doing to the PVA before trying to paint it?

PVA is an invention of the devil, plasters seem to use it everywhere, wouldn't be surprised if their put it on their cornflakes!

It is great for using under plaster and concrete but painting it is like trying to paint a teflon saucepan

If it is on the surface you have two choices, treat with a problem surface sealer like Zinsser Bullseye 123 or some suggest oil based primer. I would plump for the 123, or line the wall with lining paper as the paste will adhere well to the PVA. Then paint the lining paper.