Tim, > --prefix isn't supported for the mpfr build on x86-64, except possibly for > Ubuntu and Debian. As you snipped so aggressively, I don't know if that > might be an issue. I haven't seen an explanation of whether maintainers > of packages other than mpfr have that "preference." I apologize for snipping so agressively. I am only referring to compiling/installing GCC 4.2 on Solaris 10 (SPARC). I should have made that clear. http://gcc.gnu.org/install/finalinstall.html is where I learned of the DESTDIR jail installation. Thanks, George.