http://bugs.winehq.org/show_bug.cgi?id=20358
--- Comment #20 from Juan Lang juan_lang@yahoo.com 2009-11-05 12:21:30 --- I was mistaken in saying that the exported private key should have a leading 0 byte prepended. On the contrary, it should have such bytes omitted. I was just misreading the exported private key.
I sent a patch which corrects the issue here: http://www.winehq.org/pipermail/wine-patches/2009-November/080947.html
It's part of a series, and it depends on patch 1 of the series: http://www.winehq.org/pipermail/wine-patches/2009-November/080949.html
(The remaining patches in the series are handy, but aren't strictly needed to fix this bug.)