First off verify the current kernel
bootinfo -k
Next can your hardware support 64-bit
lsattr -El proc0
If you see any of the follwoing your ok to enable 64-bit
RS64 I, II, III, IV, POWER3, POWER3 II or POWER4
check you have the filesets installed
genkex| grep 64
should see
3e3b000 398 /usr/lib/drivers/syscalls64.ext
435f000 14648 /usr/pmapi/etc/pmsvcs
to change 32-bit to 64-bit
ln -sf /usr/lib/boot/unix_64 /unix
ln -sf /usr/lib/boot/unix_64 /usr/lib/boot/unix
bosboot -ad /dev/ipldevice
shutdown -Fr
Mike
"Whenever I dwell for any length of time on my own shortcomings, they gradually begin to seem mild, harmless, rather engaging little things, not at all like the staring defects in other people's characters."