Stig, I considered the normal earlier but like you I had my friday head on and just couldn't get enough brain power into it.
Keith, I think you have the method I'm going to use. I just need to figure out which way to go about it.
it's interesting to note that it doesn't happen with a solid, I never checked that. So, in theory, if my object is a region, then I could check the bounding box and work out a UCS from there