var Coloratore = new Class({
	initialize: function(tabellaId){		
		this.tabella = $(tabellaId);
		this.coloraRows(tabellaId);	
	},
	
	coloraRows: function(tabellaId){
	   var i = 0;
       this.tabella.getElements('tr').each(function(tr){
			    	if ((i%2 == 0)&&(tr.getProperty("class") != "header")){tr.toggleClass('grigio');	}
			    		i++;
			 }.bind(this)); 
	}	
	
});