beige G3 refusing Jaguar

I have severe trouble installing Jaguar Server on three beige G3 Desktops. They bott up fine from the CD and I can begin the installation process. Two of them get through to the end and reboot as advertised. When doing th standard post install reboot both of them hang at the openFirmware telling me "can't open: ". The bootdrive is correctly set in the OF! I've verified this, they just can't open the boot drive. (Stock 4GB IDE drive...) 384MB RAM, G3/266 no OC! The third G3 usually goes black and CPU halt in the middle of installing. It just dies, taking down the installation and the en0 interface. Again Stock beige G3/266 with 384MB RAM, 4GB IDE HD. All three machines worked flawlessly with Mac OS X 10.1 Server for a long time. Jaguar is giving me headaches... Any ideas? Thanks pepi