I was having a simular issue with a friends phone I was trying to repair for the past 2 days and today I finally got wifi access back. My problem was diffrent in the sense that I wasn't able to connect to wifi at all, the wifi toggle in the settings menu was greyed out not allowing me to even turn it on, the same thing was happening with my Bluetooth connection as well. Its a timely process with alot of steps but it worked for me. I'm going to keep it breif if you need more details in a specefic area let me know.
1st downgrade from 2.2 to 2.0 (on itunes 8)
2nd use winpwn 2.0 to create custom ipsw and pwn your itunes
3rd shift+restore custom ipsw on to your phone through itunes
You should now be on firmware 2.0 unlocked jailbroke and activated ....
4th uninstall itunes 8
5th rename itunes folder in your PC
6th install itunes 7.5
7th downgrade from firmware 2.0 to 1.1.4
8th using ziphone 3.0 unlock, jailbreak and activate
you should now be on firmware 1.1.4 unlocked jailbroke and activated.
9th using ziphone 2.6b refurbish the phone and restore locks
10th restore phone in itunes back to factory 1.1.4
at this point to make sure that everything took, insert your t-mo SIM to assure that phone is locked to factory settings.
11th upgrade itunes 7.5 back to itunes 8 (do not change the name back on your itunes folder yet.)
12th upgrade phone from 1.1.4 back up to a fresh factory 2.2
13th unlock, jailbreak and activate with QuickPwn
let me also state that this fixed my wifi but I was not able to get the bluetooth working, luckaly my friend never uses his bluetooth conection so he couldn't care less.

hope this helps ! If it does please put that thanks button to use.
Also im not sure if all these steps are actually necessary it's just the process that i went through to get it to work again.