With AIX 6.1 TL4 or newer you can use loopmount:
# ls -l *.iso -rw-r--r-- 1 root system 43974656 Jan 13 17:05 dvd_aix_profilemanager.iso # loopmount -i dvd_aix_profilemanager.iso -o "-V cdrfs -o ro" -m /mnt # df /mnt Filesystem 512-blocks Free %Used Iused %Iused Mounted on /dev/loop0 84812 0 100% 21203 100% /mnt