I have a site that has been listed in Google and dmoz for around 8 months. It has a PR of 6 and sells a software product. The PR shows up fine if I surf to it, but in the Google directory it has no PR bar on the left.
Most of the other entiries in that category have a PR entry, so I find this strange. If it was a matter of waiting for an update I would understand but it's been 8 months. I'm stumped.
Free hint: run through Google a search that you know will only show up the page in question, such as a unique phrase search. Now, check and see if the URL shows for that is exactly identical to the URL show in the Google directory. If they aren't, that is why.