yea i have done it lot of times with my earlier iPhone 4...
well before doing all this stuffs, why don't you clear all the cydia tweaks and installed them again.
I know removing all the tweaks is pain in A$$ :p ...
so what you need to do is that simply un-install Mobile Substrate from Cydia...
@webgupta - well if u had read my comment clearly , I already mentioned that its unlocked that means clearly imported.
anyways i am not here to ruin your thread/sale , again gud lck wid ur sale...;)
@webgupta - the unlocked sealed packed 4s 16gb are rolling out at 28k-30k...
so I would advise to kindly give it a look and quote your price ;)
good luck with your sale... ...