function launchPopup (launchURL,H,W,winname) {
var offset = 0;

// if it is IE on a Mac offset the size of the window
if ((navigator.appVersion.indexOf("Mac")!=-1) && (navigator.appVersion.indexOf("MSIE")!=-1)){
	offset = 16;
}

 popW = W + offset;
 popH = H + offset;
 var winLeft = (screen.width - popW) / 2;
 var winUp = (screen.height - popH) / 2;
 
 popupWin = window.open(launchURL,winname,'width=' + popW + ',height=' + popH + ',left=' + winLeft + ',top=' + winUp + ',resizable=0')
 

}