The sunfreeware gcc package is x86/32 only. To build x64 we must use the x64 gcc bundled with the os (/usr/sfw/bin)
e.g., export PATH=/usr/sfw/bin:/usr/local/bin:$PATH (sun's x64 gcc, sunfreeware's x86 gcc, rest-of-path)
Changing this allowed me to build properly. FYI - /usr/sfw/bin contains ant as well so you may need to set ANT_HOME and place it at the front of the path.
Best of luck
Peter