emulate placeholder property to browser that didn't support placeholder property it self

jquery.placeholder.js

jQuery(function() {
	jQuery.support.placeholder = 'placeholder' in document.createElement('input');
	if (jQuery.support.placeholder) return;
	
	var isEmpty = function(el) {
			return el.val().length === 0 || el.val() == el.attr('placeholder');
		},
		hold = function(el) {
			if (isEmpty(el)) {
				var e = el.get(0);
				/* // disabled feature cause of restrict to set type of password input
				if (e.tagName == 'INUPUT' && el.attr('type') == 'password') {
					el.attr('data-type', 'password');
					e.type = 'text';
				}
				*/
				el.val(el.attr('placeholder')).addClass('-no-value');
			}
		};

	jQuery('[placeholder]').focus(function(event) {
		var el = jQuery(this);
		/* // disabled feature cause of restrict to set type of password input
		if (el.attr('data-type')) {
			el.get(0).type = el.attr('data-type');
		}
		*/
		if (isEmpty(el)) {
			el.val('').removeClass('-no-value');
		}
	}).blur(function(event) {
		var el = jQuery(this);
		if (el.val().length === 0) {
			hold(el);
		}
	}).each(function(i, e) {
		var el = jQuery(e);
		hold(el);
	});
	jQuery('form').submit(function(event) {
		jQuery(this).find('[placeholder]').each(function(i, e) {
			var el = jQuery(e);
			if (el.val() === el.attr('placeholder')) {
				el.val('');
			}
		});
	});
});