Here's the thing: If you've updated your iPod Touch 3G's iOS to version 4.0.2 released a few days go, then there's NO WAY for you to Jailbreak your iPod Touch, at least, as of the moment.
We are 100% sure that the upgraded JailbreakMe solution won't work; So you best pass on that option lest you want to experience problems on your iPod Touch trying to force the issue.
What to do? Wait until a working Jailbreak becomes available.
We'll keep you posted on updates.