On solaris mounting a .iso via loopback is a little different to linux, first you need to use lofiadm to add a file as a loopback device, then you can mount it in the normal way. An example is below:

# lofiadm -a /u01/tmp/java_es_05Q1-ga1-solaris-x86-1.iso /dev/lofi/1
# mount -F hsfs -o ro /dev/lofi/1 /mnt/jes/1/