Bug 11437 jar packager: no error message but buttons disabled
20020314 on the 'jar manifest' wizard page, if you select to use existing manifest file there's no error message but next and finish are disabled user should be informed what to do to make the wizard happy
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/jarpackager/JarManifestWizardPage.java
private class UntypedListener implements Listener {
		/*
		 * Implements method from Listener
		 */	
		public void handleEvent(Event e) {
			if (getControl() == null)
				return;
			update();
		}
	}
	private UntypedListener fUntypedListener= new UntypedListener();
	
	private JarPackage fJarPackage;
	
	
	private IType[] fMainTypes;
	
	
	private Composite	fManifestGroup;
	private Button		fGenerateManifestRadioButton;
	private Button		fSaveManifestCheckbox;
	private Button		fReuseManifestCheckbox;
	private Text		fNewManifestFileText;
	private Label		fNewManifestFileLabel;
	private Button		fNewManifestFileBrowseButton;
	private Button		fUseManifestRadioButton;
	private Text		fManifestFileText;
	private Label		fManifestFileLabel;