$.fn.slideHorizontal = function(speed, step, complete) {
	var width = $(this).width();
	var overflow = $(this).css('overflow');
	$(this).css('overflow', 'hidden');
	if ($(this).is('visible') && $(this).css('display') != 'none') {
		$(this).animate({width: 0}, {duration: speed, step : step, complete : function() {
			$(this).hide()
				.css('visility', 'hidden')
				.css('overflow', overflow)
				.width(width);
			complete();
		}});
	}
	else {
		$(this).width(0)
			.show()
			.css('visibility', 'visible');
		$(this).animate({width: width}, {duration: speed, step : step, complete : function() {
			$(this).css('overflow', overflow);
			complete();
		}});
	}
};