I'm having a strange problem with one of the PowerMac G4's under my care. It's a bit of an older model, so can boot from either OS9 or OSX, except right now. When I try to boot from the Hard Drive, I get stuck at the smiling Mac screen. If I boot from an OSX boot CD (TechTool, Drive10, etc.) I can see everything fine, and the drive passes the TechTool tests with flying colours.

On the other hand, when I boot from an OS9 CD, the hard drive isn't visible at all. I can only see the CD that I am booted from. I have verified this with an older version of TechTool, Norton 7.0, and OS Install CDs.

Any ideas?