GFCI toast?

[neoh]

I was in the living room yesterday evening, and noticed that our kitchen lights turned off and on again, on two separate occasions within 10 minutes.

Then, I turned the kitchen lights off, and was heading to bed - walked by the tank the last time and just as I stepped in my bedroom I heard the 'click!' and the breaker went out.

However; here's the catch. The breaker wasn't tripped. There was no reason for the plug to stop working, as no moisture or water got involved. When I unplugged the power bar from the outlet, I actually got shocked. So, there is electricity! I'll be grabbing my meter from work tomorrow.

Turning the breaker on and off does nothing. I have to run an extension cord to the kitchen outlet to power the tank.

So. Now what? Breaker toast, or is there something else I should be worried about here?