The AIX installation media only contains packages for 5.1 and 5.3. Are other versions supported?
The AIX 5.1 packages are installed for 5.1 and 5.2, and the AIX 5.3 packages are installed for everything higher. The install.sh script detects the OS and installs the correct packages for you. You can run install.sh with the -t option and it will check for dependencies and tell you what it would install.