To create ISO:
mkisofs -U -R -J -V "OM" -o ominstall-0.2.iso om

To test ISO by mounting below /mnt/iso:
mount ominstall-0.2.iso /mnt/iso -t iso9660 -o loop=/dev/loop0,blocksize=1024
 or on RHEL4
mount ominstall-0.2.iso /mnt/iso -o loop