Haughtney,
Last time I transited DXB (early-2009), I had a 6-hour layover so hotel accommodation was provided.
This was close to, but off the airport and required immigration and customs clearance.
There was a
case not long before that of a Brit who spent the better part of 2008 in the local lock-up for having something the size of a grain of sand, caught in the tread of his shoes.
And if you need melatonin to help you sleep on your slip, well, don't. And don't have it in your bloodstream, either.