buttonsclass = function(classbutton) {
	
	//next over
	$(classbutton).append('<span class="hover"></span>').each(function () {  
		var $span = $('span.hover', this);
		
		var normal = $(this).attr("normal");
		var over = $(this).attr("over");
		
		$(this).css("background-image", "url("+normal+")");
		$span.css("background-image", "url("+over+")");
		
		fnfixpng($span);
		$span.css('opacity', 0);
		
	  	$(this).hover(function () { 
			if(!$(this).hasclass('disabled'))
			$span.stop().fadeto(500, 1);   
	  	}, function () {  
			$span.stop().fadeto(500, 0); 
		});  
	}); 
};