codice:
(function($) {
	$.fn.placeholder = function(options) {
		var that = this;
		if(!that.is('input[type=text]')) {
			return;
		}
		var defaults = {
			text: 'Placeholder'
		};
		options = $.extend(defaults, options);
		var top = that.offset().top;
		var left = that.offset().left;
		return that.each(function() {
			$('<span class="placeholder"/>').text(options.text).
			css({
				position: 'absolute',
				top: top,
				left: left
			}).insertAfter(that);
			that.focus(function() {
				that.next('span.placeholder').hide();
			});
			that.blur(function() {
				if(that.val() == '') {	
					that.next('span.placeholder').show();
				}
			});	
		});
	};
})(jQuery);
$(function() {
	$('input[name="nome"]', 'form').placeholder({text: 'Nome'});
        $('input[name="email"]', 'form').placeholder({text: 'Email'});
});