atlas G5 upgrade issue?

[Ivan Kawaler]

When I went to upgrade atlas, I found it claiming it would be  
compiling for the G4 architecture (ppc) on a G5 (ppc64) machine, and  
that it would lead to inferior performance.  I do not recall seeing  
this on previous install/upgrades of atlas.  Does atlas have support  
for the G5 architecture?  If it does, what is preventing it from  
compiling for a G5?  Does anyone know of a workaround?  I'm on a G5,  
obviously, with MacPorts 1.9.2, and gcc 4.4.6.