Thanx Tobey / Ratman, for your valuable input, want to know one thnig, is it necessary to flash with non-Sprint ROM for get rid of this issue.
Can I just unlock the phone thru Diamond Unlocker provided by Tobey (
http://forum.ppcgeeks.com/showthread.php?t=36062) then flash it with Sprint Shipped ROM (CE OS 19965 Build 19965, Radio 1.00.00F) available on the same post. Any major difference between Stock and Shipped ROM ?
Is it possible to flash with any Custome ROM (eg. Jucy Rom 4.4) then flash back to Sprint Shipped ROM, in case I'm facing issues with loaded Custome ROM. Because I heard if Radio has been upgraded then it can not be revert to previous. Please correct if I'm a victim for carrying wrong information
Note : I've already tried flashing above shipped ROM but that time phone was not Unlocked but after flashing problem was still there.