With the current namecoin price this is more of a theoretical nature. It seems it is only possible after a name_firstupdate?
Each name registered in Namecoin is associated with an address. When updating a name with
name_update operations, Namecoin wallet will automatically transfer it to a new address within the wallet.
name_firstupdate, there is no way to transfer a name to a different address (but it is still possible to register the same name a second time). However, it is possible to transfer an address to a different wallet. You would need to find which address the
name_new operation is associated with (for example, by using block explorer). Then export the private key associated with that address and import it into another wallet. Now you would be able to issue
name_firstupdate command from that wallet (you will need to use the four-argument form of the command). This will transfer the name to a different address, so the old address would not be used anymore.