Here's an interesting bit of news for the prospective iPhone developers out there. The iPhone Dev Team has recently released information on a hack they've been using that will enable the Apple phone to boot from two separate firmware versions.

According to member NerveGas, the team had actually been using this dual- boot hack for several months as a means of jailbreaking their phone.

They  decided to release the process now in light of the newer jailbreak methods that were already being developed by other groups. NerveGas used a quick example on how the hack works:

I'll walk you through a sample jailbreak scenario with 1.1.4, using 1.1.1, to show you what I mean. To do this, you will carve out a new partition on the iPhone and install version 1.1.1 on it. You'll then upgrade the iPhone to v1.1.4, which will leave the new partition intact. You can then dual-boot the iPhone, allowing you to mount 1.1.4's partition using the 1.1.1 partition. Once mounted, you'll make some changes to the mount points and install OpenSSH.

We warn users that this hack may result in permanently damaging your iPhone. You will also need a jailbroken version of the iPhone fw starting from 1.1.1 and above. The devs explained that iPhones running on 1.0.x cannot use the dual-boot hack. Now, if you're sure you can handle this hack, you'll want to read the iPhone Dev Team's step-by-step instructions over at their site via the source link.