The NEC does get revised periodically, 2002 the most recent.
The 2005 version has been out for several months.
Grounding and bonding have been revised in the last few years. In
> summary, the service entrance has to have a ground rod installed, and
> this is bonded to the electrical system at one and only place at the
> main box, this is the grounded conductor aka neutral.
A great resource on grounding and anything related to electrical work & the NEC is
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