copy uptime to /usr/local/bin/uptime and add the following lines to
/etc/rc.d/rc.0:

UPLOGBIN="/usr/local/bin/uplog"
if [ -f ${UPLOGBIN} ]
then
${UPLOGBIN}
else
echo `date +%D` Error occured during call from rc.0 or rc.6 >> /var/log/uplog
fi
