var height=0;
var width=0;
if (self.screen) {     // for NN4 and IE4
        width = screen.width
        height = screen.height
}
else if (self.java) {   // for NN3 with enabled Java
       var jkit = java.awt.Toolkit.getDefaultToolkit();
       var scrsize = jkit.getScreenSize();       
       width = scrsize.width; 
       height = scrsize.height; 
}