cforms remove weekends in datepicker

I am using cforms to create a registration form and one of the fields is a data picker. I would like to restrict the dates available in the date picker to not include weekends. I found the following jquery option to disable weekends

$("#datepicker").datepicker({ beforeShowDay: $.datepicker.noWeekends });

Since I dont want to modify the source code for cforms I would like to change the instance of datepicker after its been initialized by adding javascript to the page via the wordpress html editor with something like:

<script type="text/javascript">// <![CDATA[
$(".cf_date").datepicker('option', {beforeShowDay: noWeekends});
// ]]></script>

Can someone point out what I am doing wrong?

Copied below is the javascript cforms generates:

<script type="text/javascript">
	var cfCAL={};
	cfCAL.dateFormat = "mm/dd/yy";
	cfCAL.dayNames = ["S","M","T","W","T","F","S"];
	cfCAL.abbrDayNames = ["S","M","T","W","T","F","S"];
	cfCAL.monthNames = ["January","February","March","April","May","June","July","August","September","October","November","December"];
	cfCAL.abbrMonthNames = ["January","February","March","April","May","June","July","August","September","October","November","December"];
	cfCAL.firstDayOfWeek = "0";
	cfCAL.fullYearStart = "20";
	cfCAL.TEXT_PREV_YEAR="";
	cfCAL.TEXT_NEXT_YEAR="";
	cfCAL.TEXT_PREV_MONTH="Previous Month";
	cfCAL.TEXT_NEXT_MONTH="Next Month";
	cfCAL.TEXT_CLOSE="Close";
	cfCAL.TEXT_CHOOSE_DATE="Choose Date";
	cfCAL.changeYear=false;
	cfCAL.ROOT="http://www.dubhlinnpub.com/wp-content/plugins/cforms";

	jQuery(function() {
		if( 1||jQuery.datepicker ){
			jQuery(".cf_date").datepicker({
				"buttonImage": cfCAL.ROOT+"/js/calendar.gif", changeYear: cfCAL.changeYear, buttonImageOnly: true, buttonText: cfCAL.TEXT_CHOOSE_DATE, showOn: "both",
				"dateFormat": cfCAL.dateFormat, "dayNamesMin": cfCAL.dayNames, "dayNamesShort": cfCAL.dayNames, "monthNames": cfCAL.monthNames, firstDay:cfCAL.firstDayOfWeek,
				"nextText": cfCAL.TEXT_NEXT_MONTH, "prevText": cfCAL.TEXT_PREV_MONTH, "closeText": cfCAL.TEXT_CLOSE });
		}
	});
</script>

THANKS!