what won't work? JTextArea in a JOptionPane? Have you no imagination? This works for me...
String msg = "Tell me your deepest, darkest secret:";
JTextArea ta = new JTextArea(8, 35);
JScrollPane jsp = new JScrollPane(ta);
int res = JOptionPane.showConfirmDialog(f, new Object[]{msg, jsp},
"I wanna know...", JOptionPane.OK_CANCEL_OPTION, JOptionPane.PLAIN_MESSAGE);
if(res == JOptionPane.OK_OPTION) {
System.out.println(ta.getText());
}