I had the same problem with my Samsung Captivate running a leak version of Froyo 2.2 and tried all the previous fixes with no luck either. I knew it had to be something that was different with Froyo 2.2 cuz it worked before I updated and it worked at some of my other WiFi connections, but not my work connection which quit after the update. Same problem where it connects then trys "
Obtaining IP
Address" and doesn't then cycles back through that a few times then shows "disabled, ???". While trouble shooting the problem I noticed there was at the same time another WiFi device with a poor signal in my list that was showing up for available connection. I decided to try and connect to it and of course didn't have the password and I got it to show Disabled, Secured with WPA/WPA2 PSK and then my work connection imediately connected and has been working great ever since!
So, some how that other WiFi device in the available scan list was somehow interferring with my work WiFi. So any of you having this problem on any Froyo 2.2 device should check to see if there are others on your list in that area with an available signal that you will need to some how disable.
I hope this helps others with this problem
Thanks,
Robert