An all-devices jailbreak that will liberate the iPhone 4 from its Apple lock and permit the installation of unofficial third-party software - among other things - has been promised as imminent by one of the iPhone Dev Team, who has confirmed that the group's next release will address the fourth-generation smartphone. MuscleNerd revealed that the next jailbreak app will work in a similar way to Spirit, addressing all devices, all bootroms and the latest official Apple firmware, with a "painless install".
The exact timescale of the next jailbreak hasn't been confirmed, but it seems to be going hand-in-hand with an unlock solution for the iPhone 4. While Apple are selling unlocked versions of the smartphone in Europe, in the US the iPhone is locked to AT&T's network. So far the team have managed to inject cmd but they now need to keep that task running in the background persistently.