Since this is posted in the general subjects area I will offer the Canadian Code answer.
Bonding may be done with any approved connector, Including split bolts, marretts, 2 lugs and a bolt. Crimp or thermit welding and brazing are OK but not required.
Note that the CEC does not allow solder as a connecting material on bonding wires.
Ground wires cannot use split bolts or other removable connections.
So in Canada the bonding wire to the gas pipe can be spliced in any approved manner which I believe is consistent with the NEC.

Last edited by mikesh; 08/06/10 02:54 PM.