T-Mobile Data Network from E to circle (slower) after 4.3.1 update w/Ultrasn0w 1.2.1

[suprafitch]

My iphone 4 with 4.2.1 w/1.59.00 BB was working fine with Ultrasn0w 1.2 and t-mobile showing E (Edge) on Data network. But after I updated with 4.3.1 w/1.2.1 Ultrasn0w , my T-mobile Data network change from E to circle (GPRS) and problem with loading webpage all the time.

Anyone experience this issue?

 

[suprafitch]

Update:

Just downgraded back to 4.2.1 with Ultrasn0w 1.2.1 still have the same issue.

Therefore, this problem is likely on new version of ultrasn0w 1.2.1

Any T-mobile user that has Data plan has this issue after update to ultrasn0w 1.2.1 ?