IPhone says Locker Insert password please?

A jailbroken iphone says locker to insert a password but I have no clue what that password or even how to get rid of it!

If it's not your iphone then its none of your business what the password is. When someone jailbreaks their phone it's usually to get the extra apps from Cydia since they have really cool things not available to us normally, so the rightful owner most likely put another pass code so nosey thieves wouldn't get into it.