[gmx-users] trouble compiling gromacs-3.3.2 on OS X 10.5.1

[Scott Milner]

I'm trying to load gromacs on a new MacBook Pro, running 10.5.1 with  
latest developer tools installed.  I get an error the first time I  
run ./configure,
as follows:

configure: error: Upgrade to binutils >= 2.12.1 (or disable assembly  
loops).

whereupon configure fails.
What do I do to fix this?  (Where is "binutils" so that I can upgrade  
it?  Or what option to configure "disables assembly loops", and what  
performance hit do I take if I do that?)