I downloaded and installed the 9.0.4 update on my BW G3. When I restarted, it wouldn't boot -- the message that the ROM was too old to run with OS 9.0.4. I've reinstalled the update multiple times, booted off a CD to update, zapped the PRAM, tossed the ROM (v 3.7) and reinstalled, etc. In about 20 times to boot, I've only been successful twice. The last time I did it, I was actually trying to boot from an 8.6 OS partition, so I held the OPT-CMD-SHIFT-DELETE keys. Lo and behold, the 9.0.4 partition booted properly.
Does anybody have ANY idea what's going on? I've been using Macs for over 10 years, and I don't recall a situation like this.