check out this link. this might help u to downgrade.
http://www.redmondpie.com/downgrade-iphone-3.1-to-3.0.1/
and if u want to JB ur iphone, check out this link too. it works for me:
http://www.redmondpie.com/sn0wbreeze-3.1.3...e-3g-3gs-3.1.3/
Apple iPhone <WTA> Anyone Know Repair Iphone, Iphone 3gs 3.1.2 16gb Problem
Feb 10 2010, 10:55 PM
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