jquery.placeholder.js

(function ($) {

    $.fn.placeholder = function (_options) {
        var defaults = {
                blank: '',
                className: 'default'
            },
            options = $.extend({}, defaults, _options || {});

        return this.each(function () {
            var node = $(this);

            if (!Modernizr.input.placeholder) {
                var placeholder = node.attr('placeholder');

                // Don't bind the placeholder events more than once.
                node.unbind('.placeholder')

                if (node.val() === options.blank || node.val() === placeholder) {
                    node.val(placeholder).addClass(options.className);
                }

                node.bind('focus.placeholder', function (event) {
                    if (node.val() === placeholder) {
                        node.val(options.blank).removeClass(options.className);
                    }
                });

                node.bind('blur.placeholder', function (event) {
                    if (node.val() === options.blank || node.val() === placeholder) {
                        node.val(placeholder).addClass(options.className);
                    }
                });

                node.closest('form').bind('submit.placeholder', function (event) {
                    if (node.val() === placeholder) {
                        node.val(options.blank).removeClass(options.className);
                    }
                });
            }
        });
    };

})(jQuery);