As promised, here is JD's Passport updater updated to work for gd5. This is a temporary fix, however. Just follow the instructions to get it to working for you. Here is the code...
EDIT : I editted the previous one for a reason. Sorry warrior, you did a good job, but i don't want to expose people to things that i myself am not fully aware of. JD may have done a good job and that, but till i understand how he got it to work, and till i am 100% sure that it is safe (as he uses a proxy, it can easily use a cron job to store people's account details), i do not want people running around with it.