Stucked at logo: ios 4.2.1, iphone 3gs, ipad baseband, unlocked with ultrasn0w 1.2
After lot of calculated decision I stepped ahead to fuse ipad baseband and unlock iphone 3GS on 4.2.1 OS. my phone is freeze now at logo.
a) Updated unlocked iphone 3gs with 4.2.1
b) Jailbreaked with redsn0w, install cydia and ipad baseband
c) Rebooted phone in teatherd boot mode
d) Opened Cydia and installed ultrasn0w 1.2
e) Rebooted and then STUCK at apple logo
Next Step: Since nothing was happening then I tried restoring original IPSW 4.2.1 by going in DFU mode via ITUNES, it started well but later gave error 1015 (I read somewhere that it is common)
Current State: After restore failed phone is always in recovery mode.
I dont have SCSH or any file backed up.
Can I use any custom IPSW to escape?
Is there anyway I can go to 3.1.3 firmware?
I have noticed loads of post with same things but none has problem like me. :spinme