I have a swing app that has been developed on Windows XP, and I'm using
    System.setProperty("java.awt.Window.locationByPlatform", "true");
to make the windows use the default XP placement algorithm. This works a treat, but when I deploy the application on Win98 the windows appear correctly the first time the application is run, but on subsequent runs they are drawn completely off-screen - the application shows up as an icon in the Windows taskbar, but it's not visible. I initialy thought this might be due to me using Webstart to deploy the app, but it's the same if I run it directly. Something that might be relevant: I'm running the app under the Windows L&F using
    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());

I've tried setting the positioning on a per-window basis using
    setLocationByPlatform(true);
before the window is setVisible(), but that has no effect either.

I do have a workaround, but it's inconvenient as it means I have to add it to each of my application windows, if I make a call to
    setLocationRelativeTo(null);
or
    setLocationRelativeTo(parentWindow);
as appropriate, then the behaviour is as I expect - centred for the case where the window parameter is null, and positioned relative to the parent window otherwise.