swing works in JBuilder, not in .JAR file?

[arik]

I have made application using JBuilder 6 (JRE 1.3)
Operating system WIN XP (JRE 1.3)

When I run application in JBuilder evrything works fine.

Now I made executable .JAR file using JBuilder
(wizard -> archive builder -> application)

When I executed the .JAR file the background color on JButton (javax.swing)
didn't work. (it's always white).

On AWT button colors are OK.

What I have made wrong?

JPanel contentPane;
JButton jButton1 = new JButton();
Button button1 = new Button();
...

//Component initialization
contentPane = (JPanel) this.getContentPane();
contentPane.setLayout(xYLayout1);
....

jButton1.setBackground(new Color(220, 240, 250));
button1.setBackground(new Color(220, 240, 250));
....
contentPane.add(jButton1, new XYConstraints(99, 100, 158, 30));
contentPane.add(button1, new XYConstraints(65, 164, -1, -1));