jQueryAutoCompleteHiddenField.js

<script type="text/javascript">
$(function() {    
    $(".autocomplete").each(function() {
		$(this).autocomplete({
			source: "index.cfm?action=admin:main.lookup&src=" + $(this).attr("data-src"),
			minLength: 2,
			select: function(event, ui){
				var thisObj = $(this);
				var thisId = "#" + thisObj.attr("id");
				
				//console.debug(thisObj);
				//console.debug(thisId);
				
				//remove existing value
				$(thisId + "-value").remove();
				
				$("<input />")
					.attr("type","hidden")
					.attr("id",thisObj.attr("id")+"-value")
					.attr("name", thisObj.attr("id"))
					.attr("value", ui.item.id)
					.insertAfter(this);
			}
		});
	});
});
</script>

<input id="test1" class="autocomplete" data-src="DataSourceToUse" />