3GS can't restore from Jailbroken

Hello,

I just got a 3GS and it was jailbroken when I got it. Since I don't want a JB'd phone, I went to restore within Itunes but it keeps saying it can't do that "build". I've tried some customer IPSW files for older versions of iOS, but those keep giving me the errors (1601, 20 etc). One of the problems is that I didn't check what firmware version the phone was one before I first plugged it in so I don't know that.

Thoughts??

huff

I don't know why you wouldn't want a jb phone, anyhow, download RecBoot 1.0.2. That will put it in recovery mode for itunes. If they upgraded to the ipad baseband, put it on craigslist. if nothing else....Have you tried the iREB fix?
Fix 1604, 1601, 1600, 16xx Error During iOS 4.1 Custom IPSW Firmware Restore in iTunes with iREB 4.1 | Redmond Pie
good luck....