I really like my Kühl Liberator pants (
http://www.kuhl.com/kuhl/mens/pants/liberator-convertible/), even though they are a mens, they fit me very well, and they can convert into shorts (but the zipper is very well hidden). Decent amount of pockets and they dry quick. I wear them not only for kayaking but out and about too. They are a little pricey so look for good sales, i don't by them unless i can find them for cheaper, $50 was the best deal i found so far, but that was when Gander Mt. was going out of Business...
With that said, i find that any quick dry pants can do the job for kayaking. They are typically a lighter fabric, will protect you from the sun, and dry quickly when they inevitably get wet.