A very long while ago, Apple released Java SE 6.0 Developer Preview 2 on the Apple Developer Connection. It looks like this may be the only way to get JRE 6.0 working on PowerPC Macs, since Apple opted to not provide that program to PowerPC users.
Does anyone still have a copy of this? I can't find it anywhere on Apple's website now, and I would really like to get my hands on it. Thanks!