Bug 28510 java build path inconsistency [build path]
20021216 select rt.jar in the package explorer open properties it allows you to set the javadoc location but for source attachment you are sent somewhere else it's inconsistent - on the java build path they both look sort of the same (they sit under the same node in the tree)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/buildpaths/SourceContainerWorkbookPage.java
private final Object[] EMPTY_ARR= new Object[0];
		
		
		public void customButtonPressed(TreeListDialogField field, int index) {
			sourcePageCustomButtonPressed(field, index);