There's a writeup somewhere on the net about applying grease to the right spot to make the noise go away, I don't remember where, but if you search google you'll likely find it.

I think mine only makes the noise in the summer when it's humid, or at least only when warmer out. It doesn't bother me, many cars' clutch pedals make that noise at times.

edit: here it is http://www.honda-tech.com/zerothread?id=179021 forgot I had it bookmarked h:

Can't say for sure that's the cause on your particular car, but good luck.