many internal improvements have been made to the syscall-related code
in preparation for porting to x86_64 and other archs.
-upcoming 0.6.0 - x86_64 port, various important fixes
+0.6.0 - x86_64 port, various important bugs fixed
new x86_64 (amd64) architecture port, contributed by Nicholas J. Kain,
along with PORTING guide. source tree layout and build system have