1. Install the latest version of Java (1.4.2) from Sun's site. You've probably tried this.
2. Download this Java Registry patch for Firebird.
3. Double-click that file to add a single key to your registry.
4. Restart Firebird

Simple, huh? Firebird is a hell of a lot better documented than Mozilla ever was.

Also, try browing Amazon like you never have before. This UI takes a while to get used to, but wow, that's functional. I love innovative HCI.