function openAWindow( pageToLoad, winName, width, height, topmargin, leftmargin, center){

xposition=0; yposition=0;
if ((parseInt(navigator.appVersion) >= 4 ) &&(center)){
 xposition = (screen.width - width) / 4;
 yposition = (screen.height - height) / 3;
}

args = "width=" + width + ","
+ "height=" + height + ","
+ "topmargin=screen.width/2"
+ "leftmargin=screen.height/2,"
+ "location=0,"
+ "menubar=0,"
+ "resizable=0,"
+ "scrollbars=0,"
+ "status=0,"
+ "titlebar=0,"
+ "toolbar=0,"
+ "hotkeys=0,"
+ "screenx=" + xposition + "," //NN Only
+ "screeny=" + yposition + "," //NN Only
+ "left=" + xposition + "," //IE Only
+ "top=" + yposition + ","; //IE Only

window.open( pageToLoad, winName, args );

}