@tofubean/@pdagenius: No, you need to run the uninstallers (of course, the jailbreak being the last thing you need to uninstall), a reset to factory defaults won't uninstall the hacks, it'll just disable them.
@Markstar: Yifanlu's 0.5.1 won't run on anything other than FW 3.2.1, which explains what you're experiencing

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