void renameValue(int nTargetNode, String sValue) {
		String sNewValue = (String) JOptionPane.showInputDialog(null, "New name for value " + sValue, "Node "
				+ m_BayesNet.getNodeName(nTargetNode), JOptionPane.OK_CANCEL_OPTION);
		if (sNewValue == null || sNewValue.equals("")) {
			return;
		}
		m_BayesNet.renameNodeValue(nTargetNode, sValue, sNewValue);
	    m_jStatusBar.setText(m_BayesNet.lastActionMsg());
		a_undo.setEnabled(true);
		a_redo.setEnabled(false);
		repaint();
	}