I had the same problem today – I installed the Java Developer package from http://connect.apple.com, but couldn’t find “src.jar” in /System/Library/Frameworks/JavaVM.framework/...
anymore. On my machine, it’s now
in
/Library/Java/JavaVirtualMachines/1.6.0_22-b04-307.jdk/Contents/Home/src.jar
.
Update: For the latest version from March 2011, the jar is now:
/Library/Java/JavaVirtualMachines/1.6.0_24-b07-334.jdk/Contents/Home/src.jar
Once again, you’ll have to download the new Java Developer package first.