This bug is reproducible on Windows.

Following are the steps to reproduce the defect.
 1.Create a frame with iconified state ----f.setExtendedState(Frame.ICONIFIED) and do not make it visible
 2.Create FileDialog with above frame as parent.
 3.call fileDialog(Visible)

 Expected Result: making file dialog visible should not Display frame
 Actual Result: 1.It dislplays Frame (even though it is not visible) you can deiconify this frame,
                2. frame.isVisible() returns false.
3. Alt + Tab dislplayes both frame icon as well as Dialog icon.

Same defect can be reproduced using following scearios.
                
1.Creating Window with frame as parent is Displaying frame and isVisible should return false.
  and alt tab should have only frame ICON.
2.Create A undecorated frame as iconified state and setVisble(false) and create a Dialog.
making the dialog Visible actually creates a Frame in iconified state.
The following code easily reproduces the bug:

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import java.awt.Frame;

public class Test {
    public static void main(String[] args) {
        Frame f = new Frame("Parent");
        f.setExtendedState(Frame.ICONIFIED);
        f.pack();
    }
}
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