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
protected void sourcePageDoubleClicked(TreeListDialogField field) {
		if (field == fFoldersList) {
			List selection= fFoldersList.getSelectedElements();
			if (canEdit(selection)) {
				editEntry();
			}
		}
	}
	
	
	protected void sourcePageCustomButtonPressed(DialogField field, int index) {
		if (field == fFoldersList) {
			if (index == IDX_ADD) {
			List elementsToAdd= new ArrayList(10);
				if (fCurrJProject.exists()) {
					CPListElement[] srcentries= openSourceContainerDialog(null);
					if (srcentries != null) {
						for (int i= 0; i < srcentries.length; i++) {
							elementsToAdd.add(srcentries[i]);
						}
					}						
				} else {
					CPListElement entry= openNewSourceContainerDialog(null);
					if (entry != null) {
						elementsToAdd.add(entry);
					}
				}
				if (!elementsToAdd.isEmpty()) {
					if (fFoldersList.getSize() == 1) {