Then, I noticed the following statement at Spirit website.
- Spirit is an untethered jailbreak for iPad, iPhone, and iPod touch on certain firmware versions.
- Spirit is not a carrier unlock.
- If you currently are using a tethered jailbreak, you have to restore to use Spirit. Do not upgrade if you use an unlock on an iPhone 3G or 3GS. (You can, however, restore to 3.1.2 if you have SHSH blobs for that version.)
- (If you mistakenly ran Spirit despite using a tethered jailbreak, try these instructions.)
- Any iPad, iPhone, or iPod touch on firmware 3.1.2, 3.1.3, or 3.2.
- An activated device: one not stuck on the Connect to iTunes or Emergency Call screen.
- Any version of iTunes 9 earlier than 9.2
- Syncing with iTunes before trying this is highly recommended.