The later iBooks, PowerBooks, and PPC Mac Minis came with 2 install disks: one for OSX and another for support programs (iLife) and Classic support. There's probably something similar for that machine, albeit on CD rather than DVD.
If you can find the disk or an image, just pop it in and run the installer. Once Classic is installed, just run your program, OS9 will boot, and your program will start. Pretty impressive software engineering, I think.
