I'm having the same problem as you Tank. Don't bother contacting Samsung customer support, they're about as helpful as a sack of potatoes.
Convo with Samsung:
Please wait for a Samsung Agent to respond.
You are now chatting with 'Vick'
Vick: Hi, thank you for contacting Samsung Technical Support. How may I help you today?
Visitor: Hi, I'm having a problem with Kies mini. In the firmware version slot it says unregistered device. I'm not sure what I could do about that.
Visitor: I'm on a samsung vibrant T959
Vick: I understand that you are unable to connect to Kies mini, am I correct?
Visitor: Right.
Vick: Thank you for confirming.
Vick: I apologize for the inconvenience.
Vick: Just to confirm, may I know the exact error message while you connect the phone?
Visitor: It just says that my device is unregistered in the firmware version slot.
Visitor: I understand there is an update available for my brand of phone and because of this I can't download it.
Vick: Thank you for confirming.
Vick: Just to confirm, did you register the phone with Samsung Website?
Visitor: Just did, about 5 minutes ago.
Vick: Just to confirm, did you register using Serial number or IMEI number?
Visitor: The IMEI number.
Vick: Just to confirm, are you able to login to Samsung using the phone?
Visitor: On the Samsung website through the phone?
Vick: I'm sorry. Not on the phone on the website.
Visitor: Yes, I am logged in right now.
Vick: Just to confirm, did you receive any notification on the phone regarding the update?
Visitor: No, it's an update through Kies mini that everyone seems to be receiving for Froyo 2.2. Everyone besides me and a few others, and the common denominator as to why we aren't getting it is because of the unregistered device problem.
Vick: I'm sorry. I see that yo may update only if you receive any notification on the phone. You need to tap on the notification to update the firmware on the phone.