ziphone has pretty much been out of the scene for a while now, everyone's using either PwnageTool, Quickpwn (for the 1st gen touch) or redsn0w (for the 2nd gen). All of these require 2.2.1 to be installed - the downside is it costs $10 to upgrade. The upside - the ability to jailbreak, bug fixes, new features, plus being able to download apps from Apple's own App Store.