westfw:
The source at Google Code Archive - Long-term storage for Google Code Project Hosting. has been fixed, and I've added a .hex file for 644p to the download area.It's still tagged as v4.5, since this didn't change any object code of previously supported platforms. And like the 1284p support, the 644p is not an official Arduino team platform, so this won't be committed to the Arduino repository until it's time for some sort of big "upgrade."
Yeah, cool, thanks!
Did you fix the problem with the second UART too?