This will seem odd, but I wanted to share it to help others out.
My car (2002, 125,000 miles) was showing this code a several months ago. (I didn't get a CEL, but I have an Ultragauge and it came up as a pending code). I tightened the gas cap a few clicks and it stopped a few days later. Then it came back and I again tightened the cap and it did not go away. This time, I took the cap off and noticed a lot of grime and dirt on the filler neck where it meets the cap. Wiped that and the sealing O-ring on the cap off with a paper towel, and put the original cap back on and so far I haven't seen the code again.
UPDATE: The above turned out to be short-lived. I'm getting the pending code again, but it doesn't happen consistently, so it's a pain to track down - I'll probably replace the fuel cap first.
UPDATE: 31Mar2013 - New fuel cap fixed it for me ... so far, at least!!!
Last edited by Tiger-Heli; 04-01-2013 at 04:58 PM.