SwingTextField background not working

Changing the background of a SwingTextField in FX 1.2 does not seem to work. Here is the code snippet:

package swingtextfield;

import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.ext.swing.SwingTextField;
import javafx.scene.paint.Color;

Stage {
    title: "SwingTextField background not working!"
    width: 350
    height: 100
    resizable: false
    scene: Scene {
        content: [
            SwingTextField {
                width: 300
                height: 50
                background: Color.YELLOW
                foreground: Color.GREEN
            }
        ]
    }
}