XBMC identifies trailers as movies!

I don't kn ow what I've done wrong, but XBMC is identifying some of my trailers as the movie "Trailer War" - so my recently added and my movie library has several instances of that film listed.

The original metadata and trailer downloads are handled by an external program called Media Center Master - that has been configured to create XBMC meta data, and in the main this seems to work well. I have no problems at all with TV Shows, and most of the Movies are ok too. Yet sometime trailers are identified as "Trailer War".

My XBMC is running on W7 64bit, the trailer are names like "G.I. Joe, The Rise of Cobra (2009)-trailer.mov"

Any ideas what I can check on my XBMC configuration?

thanks