On Line 318, inside the prop function, we are checking "if ( value.constructor == Number....".

This could throw an error in some scenarios where value has no properties at all.

For me, this happened here,

$(document).ready(function() {
	$("form.valdiate").each(function() {
			$(this).attr({ target: $(this).attr("onsubmit")});  // very weird way for a callback after form validation:)
			$(this).attr({ onsubmit: ""});
			$(this).validate();
	});
});