function wm_Popup(strUrl, strTarget, strWidth, strHeight, strFeatures, boolOverwrite, boolReturnHandle){
	//var width = (strWidth == null || strWidth = "") ? window.screen.availWidth * (3/4) : strWidth;
	var width = window.screen.availWidth * (3/4);
	var height = window.screen.availHeight * (3/4);

	if (strWidth != null) {
		width=strWidth;
	}
	if (strHeight != null) {
		height=strHeight;
	}
	
	//place in the middle:
	var posLeft = (window.screen.width - width) / 2;
	var posTop = (window.screen.height - height) / 2;

	var url = strUrl;
	var target = "_blank";
	var features = "scrollbars=auto,resizable=no,width=" + width + ",height=" + height + ",left=" + posLeft + ",top=" + posTop;
	var overwrite = false;
	var returnHandle = true;
	
	if (strTarget != null){
		target = strTarget;
		if (strFeatures != null){
			features = strFeatures;
			if (boolOverwrite != null){
				overwrite = boolOverwrite;
				if (boolReturnHandle != null){
					returnHandle = boolReturnHandle;
				}
			}
		}
	}

	handle = window.open(url, target, features, overwrite);
	if (returnHandle){return handle;}
}