[R-SIG-Mac] problem including jpeg & png support for R-2.2.1 under OS-X on G5s

[Stephen Shiboski]

For some reason, my builds of R (OS X 10.4.4, gcc 3.3) on our G5  
machines
aren't picking up these libraries (as evidenced by the output of the
capabilities() command), even though they exist and check out
as OK in config.log.

However, the G4 builds include both. The only difference I see  in  
the configurations
are the use of G5-specific optimization flags on the G5s:
     CFLAGS='-mcpu=970 -mtune=970 -mpowerpc64 -mpowerpc-gpopt'


Any suggestions appreciated.

-SS