Unfortunately, you can't extend an ungrounded circuit, so you have created a violation there.
This is news to me?
406.3(C) FPN clearly references 250.130 for doing just that. And 250.130 say's:
For replacement of non–grounding-type receptacles with grounding-type receptacles and for branch-circuit extensions only in existing installations that do not have an equipment grounding conductor in the branch circuit, connections shall be permitted as indicated in 250.130(C).
As for the plug in tester yes it does use the grounding conductor to trip the GFCI but pay no attention to it as the button on the GFCI is the only UL listed way to test a GFCI or AFCI.
[This message has been edited by hurk27 (edited 03-22-2005).]
