jquery.placeholder.js

(function($) {
	$.support.placeholder = 'placeholder' in document.createElement('input');

	$.fn.placeholder = function() {
		var supported = $.support.placeholder;
		if (!supported) {
			this.each(function() {
				var input = $('input[placeholder]', this);
				if (input.length) {
					var placeholder = $('<div class="placeholder">' + input.attr('placeholder') + '</div>')
						.insertBefore(input)
						.click(function() {
							placeholder.hide();
							input.focus();
						});
					input
						.blur(function() {
							if (!input.val()) {
								placeholder.show();
							}
						})
						.blur();
				}
			});
		}
	};
})(jQuery);