[...]

I believe (but could be wrong) that JDK 1.4(.x) is the first version where
Sun offered a 64-bit SPARC Solaris JVM.

By default the C compilers generate 32-bit code, so presumably you chose
64-bit mode explicitly?

Is there something about your library that desperately needs 64-bit SPARC
code?  The vast majority of apps (and particularly Java apps) still run in
32-bit mode, and unless you really need an address space larger than 32
bits, you're probably paying a bit of a performance hit for using 64-bit
mode (this isn't just for SPARC;  note that a lot of the SPEC benchmarks,
even on very 64-bit-oriented CPUs like the Alpha, are run in 32-bit mode
because they perform somewhat better that way).

This probably goes without saying, but just for the record...  even if you
use the 64-bit Solaris kernel (and hence 64-bit kernel device drivers),
it's still fine for the user-level application programs (and libraries) to
be 32-bit (and on the average Solaris 8 or 9 system, chances are that 90%
or more of the apps are running in 32-bit mode).

Thomas Maslen
maslen@pobox.com