function openWindow(sUrl, sName, iWidth, iHeight, sFeatures) { 
	if (arguments.length < 5){
		alert('openWindow requires 5 arguments');
		return false;
	}
		
    if (document.all) 
        var xMax = screen.width, yMax = screen.height; 
    else 
        if (document.layers) 
            var xMax = window.outerWidth, yMax = window.outerHeight; 
        else 
            var xMax = 640, yMax=480; 

    var xOffset = (xMax - iWidth)/2;
    var yOffset = (yMax - iHeight)/2; 

        sFeat = sFeatures.toLowerCase();
        
        if (sFeat.indexOf("toolbar") > -1){
			yOffset = yOffset - 30;
		}
        if (sFeat.indexOf("location") > -1){
			yOffset = yOffset - 30;
		}
        if (sFeat.indexOf("menubar") > -1){
			yOffset = yOffset - 30;
		}
        if (sFeat.indexOf("status") > -1){
			yOffset = yOffset - 30;
		}
		
		if (yOffset < 0){
			yOffset = 0;
		}
        
        if (iWidth != -1){ 
                sFeat = sFeat + ',width=' + iWidth + ',height=' + iHeight 
                sFeat = sFeat + ',screenX='+xOffset+',screenY='+yOffset+',top='+yOffset+',left='+xOffset 
        } 
        
    window.open(sUrl,sName,sFeat); 
}