As recently Apple has released iPhone OS 3.1 on Rock and Roll event. So, the most frequent question which is asked by jailbroken iPhone owners is that either the upgrade to new iPhone OS for jailbroken devices is safe or not? The iPhone Dev Team already answer this question that the users with jailbroken or unlocked iPhones should not upgrade their devices to OS 3.1.
“It’s safe to update iTunes if already jb/unlocked. Just don’t update iPhone firmware too!”
This is the recommendation of iPhone Dev Team to users of jailbroken and unlocked iPhones that they should wait for the new releases of jailbreak tools until then they’ve to stay with their old iPhone OS.