I think I have exactly the same issue as you. I started by posting on the SF forums:
viewtopic.php?t=15792
(Sorry I can't post real links yet)
So I am interested in what is going on here.
Mine blinks like yours, so I'm guessing that it is functioning correctly, and I am assuming that it was preloaded with the sk bootloader.
I do see the blinking stop as soon as the serial starts, so I think it is safe to assume that the DTR - Reset function is working.
I don't know, but I think we have the same problem.
Kyle