MSFTGuy and Push Fix dev managed to fix Blacksn0w and firmware 3.1.3 and released a modified version of BlackSn0w that will add support for iPhones running 3.1.3/ baseband 05.11.07 and, it also fixes a small bug that appears to make WiFi much more stable.
push fix
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Possible Fix for Push Notifications on Hacktivated iPhones
Got a hacktivated iPhone? Missing out on push notifications for those IM apps? We may have found a solution.