I am trying to turn my PC into a dedicated single-purpose controller for a project. Basically, I want to automatically start an interactive command-line program upon boot. Putting a line in /etc/inittab starts the program, but then the prompt shows up afterward. How can I autostart the program late enough in the boot process to "absorb" the prompt?

Details:
KNOPPIX 3.4 (recompiled, but still vanilla 2.4.26)
HD installed
Default runlevel 1 (necessary for quality-of-service reasons)