$(document).ready(function() {
	
	// a custom method making the default value invalid
	jQuery.validator.addMethod("defaultInvalid", function(value, element) {
	    return value != element.defaultValue;
	}, "");

	jQuery.validator.addMethod("minchecked", function(value, element, param) {
	     var noOfChecked = $("#[id*='option_']:checked").length;
	          return noOfChecked >= param;
	}, jQuery.validator.messages.minchecked );

	jQuery.validator.addMethod("minchecked_category", function(value, element, param) {
	     var noOfCheckedCat = $("#[id*='category_']:checked").length;
	          return noOfCheckedCat >= param;
	}, jQuery.validator.messages.minchecked_category);

});