In reply to Jaz Gandhu:
I had the same problems with two empty fuel bottle on Hawaii. At the end we send the fuel bottle by a parcel service on the airport (for them was it not a danger thing, so it was transported by a person-airoplane!). When we returned to the checking, there checked our bags by x-ray, but doesn't find other metal bottles!!!
The best thing is to wash out the fuel bottle with water and chemie and mark the bottle as a drinking bottle and not a fuel bottle. Perhaps it works. And tell them, that you cock with gas and you don't have any gas bottle with you.
markus