I dont know who you have spoken to mate, but I had a long conversation with Paul Mummery our FAO from Leicester today 6/02/09 on the exact same subject.
Paul assures me that FOX IS VERMIN, it has no off season, as ground game does and there are people that shoot them with .22 in London gardens and charge £300 a night and quoted a channel 4 program on city fox control . I certainly won't have a problem shootng them with my .17 or .22lr if they are close enough to kill cleanly.
Hope that has cleared up all the doubt, and if it says vermin on your licence you can shoot them, at least you can