function centerWindow(adress) {
if (document.all)
var xMax = screen.width, yMax = screen.height;
else
if (document.layers)
var xMax = window.outerWidth, yMax = window.outerHeight;
else
var xMax = 600, yMax=450;
var xOffset = (xMax - 600)/2, yOffset = (yMax - 450)/2;
window.open(adress, "Popup", 'scrollbars=yes,menubars=no,toolbars=no,resizable=no,width=600,height=450,screenX='+xOffset+',screenY='+yOffset+',top='+yOffset+',left='+xOffset+'');
}