ECN Forum Forums General Topics of the Trade General Discussion Area GFI outlet in conjunction with GFI breaker??

I have a customer who has a house built in the 70's that has a 20 GFI breaker that feeds a lot of stuff from the house then a lot of lights down at the lake he lives next to
(Jecuzzi, path lights, boat house lights etc.). He's wanting me to add an outlet down near the lake and installing a GFI in it also. Any problems adding it on the same circuit as the breaker?? I think I've run into this before and had no problems, but can't remember. Thanks Steve..