wtmp cleanup procedure

cd /var/adm/
/usr/lib/acct/fwtmp < /var/adm/wtmp > /tmp/wtmp.tmp
cp /tmp/wtmp.tmp /tmp/wtmp.bak
cat /dev/null > /tmp/wtmp.tmp
/usr/lib/acct/fwtmp -ic < /tmp/wtmp.tmp > /var/adm/wtmp
mv /tmp/wtmp.bak /var/adm/wtmp.old