Phone systems are a Chapter 8 installation. The rules in Chapters 1-4 do not apply unless specified in the Chapter 8 article. The only requirement for conduit grounding is on the line side of the primary protector. See 800.12(C). The only requirement (800.48) for interior conduits on the building side of the protector is that the raceway be installed per the Chapter 3 article that applies to that raceway. The grounding requirements for raceways are in Arcle 250, not Chapter 3, so grounding is not required by the code.
[This message has been edited by resqcapt19 (edited 04-29-2003).]