its possible with JB as I just restored to 4.1.2 last week cause my device was acting up. what I did was use flash cwm via Odin and booted back into the os, I didn't have the ICS flashable su so I used chainfires supersu 2.0.1, booted back into the os followed going back to recovery and flashing cwm 220.127.116.11 I believe rebooted recovery and flashed a KitKat ROM.
Sent from my Half Baked Vibrant
---------- Post added at 04:57 AM ---------- Previous post was at 04:29 AM ----------
I got it i used vroot , gave me root , installed rom manager flash cwm voila!
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