Apologies, but if you registered on or after November 27, 2009, please do so again.  I had to delete all of the users between then and now due to a rash of spam registrations.  Most were obvious spam but there were a few I was iffy about.  However, concerning the timing, I went ahead and deleted them, figuring a real user who wanted an account would be back soon.  Sorry for any inconvenience!  I also installed a plugin so that new registrations require a captcha code to complete the form so this should not be a problem in the future.