walkman - 3:02 pm on Jun 29, 2008 (gmt 0)

>>If the name is that unique, and the client now have an SM, does the client have some sort of rightful claim to the .com version since it has been parked and unused for so long?

IMO it's not retroactive. He bought the name long before you got your trademark. This is called reverse domain hijacking and will fail.