Just a "heads up" - I just tried using the official OKI driver (i.e., this one), and found that I couldn't get the duplex to work. After fighting with it for a while, I used Easterly Wind's .ppd (the one posted at the beginning of this thread) and voila, duplexing worked. So, many thanks to Easterly Wind for the wonderful work - try his/her driver first!
B410d on 10.04 Lucid
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