Any marriage in a country other than your own often isn't recognized legally. I'm married to a Brit. We married in the UK. The marriage isn't recognized in the US until you file a load of paperwork. Some people never even bother!
Really, vicki? That's interesting. The only thing I knew was that prenup agreements don't "work" in Britain. So, technically, if a husband and wife were from two different countries they would have to marry (though the act or paperwork) twice?