21st
Java 1.5 in OS X Lion
Update: Ben Morin has improved on the Snow Leopard method to get Java 1.5 working on OS X Lion. Great news!
Why would anyone want to go through all that just to get Java 1.5? There are plenty of applications out there (my beloved Zend Studio 5.5 is one of them) that are stuck at 1.5 because vendors have either disappeared or have moved on in incompatible directions.
One of these days I’m going to write an essay about the long-tail downside of the software lifecycle, which is a secret productivity killer. Open source your old applications and old builds — don’t just abandon them. I’d much rather fix the display bugs in Zend Studio than keep having to use Java 1.5 from Leopard.