i got my s2 a few weeks ago and used his method to root my and my wifes s2 and had no problem what so ever so i dont understand what the deal is... and yes the firmware version on mine and my wifes phone was 2.3.6
That means you tripped the flash counter which most people try to avoid, a well as if someone stays on 2.3.6 then they won't have wifi on his kernel.
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