I work for a US company but my reporting line is into the UK and my HR support is also provided from the UK. it scares me when I see the sheer level of ignorence that exists to us over there. I have spent hours at a time explaining Irish history, that the queen is there queen, not ours and that just because something happens on "the mainland" does not mean it applies over here. This is especially the case for HR and even more so where things like contracts are issued by "shared service" type structures who can be based(in my case) out of India.,
You probably just need to educate them and indeed it can be quite entertaining watching them make complete and utter eejits of themselves.