Thanks Mary - I didn't have chance to check onto Steve's profile before work this morning, so I assumed that the query was the one he had raised in the post
I've had a look at the one you've linked to and @Steve - I'm sorry I'm not able to answer that one myself as I've not come across it before, but hopefully someone will! Like I said, I'm very sorry that you have found that not to be the case on this occasion and perhaps someone will be able to shed some light for you soon.
Richard