[Arran]

 I was looking for the name of the chemical they used to terminate termites, it's methyl bromide, it is, or was used for tent fumigation of a house. I think what is needed is a way to kill the eggs, which a lot of the suggested things will do, the residual effect is what you need to prevent re-infestation. The microwave idea will kill the eggs too, but there is definately no residual protection there either. Maybe the wood could be coated with a boric acid solution, that stuff kills carpenter ants and other insects, or a copper based solution.
Regards
Arran