Hi there I have just got the same type of letter wanting me to use my surname so that they can have a "diplomatic consignment" released valued at $us 8.7 million.
The person who left it was drowned along with his wife and all members of his family in the Boxing Day Tsunami. If it is not claimed then the whole amount is confisicated.
The letter came from CBL LAWYERS & PARTNERS Madrid Spain and Don Bufete Leon is the "Lawyer" handling the case.
I was first suspicious even before I opened it as there was no return address on either the front or reverse of the envelope.

Marcus D.