<!-- 
function Validate(form) { 
    var v = new RegExp(); 
    v.compile("^[A-Za-z]+://[A-Za-z0-9-_]+\\.[A-Za-z0-9-_%&\?\/.=]+$"); 
    if (!v.test(form["url"].value)) { 
        alert("ERRORE: Inserire un URL valido!"); 
        return false; 
    } 
} 
//-->