I've had the problem on my 8900 before, too, don't actually use it, since I like Opera Mini 4.2 more. Not sure why it happens, but it does. Very annoying in my opinion.
I can tell you every version from 330 on it doesn't work. It never worked for me on my 8900 so I just got accustomed to it. It would be nice if it worked, but oh well.
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I've since deleted opera mini 5.0 beta, given up on skyfire. Now I'm down to opera, the stock browser and Bolt with no functional back button.
For whatever reason, bolt seems the best overall for me. I've always had trouble with the opera renders a page. I've sent letters off to support let's hope one day they act on it.
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