I tried to use IntelliJ 6 for OS X, but it insists on needing JDK 1.5/5. But according to the KnownIssues.txt file, JDK 1.4 should work fine. Does anyone have a definitive insight into which JDK version works?
Yes, the info.plist file in the application bundle actually specifies that "JVMVersion" must be "1.5+", which means anything below 1.5 wouldn't work. I guess it's time to get with the program and start using Java 5.