function checkcontacts (form){
var mailstring = form.submit_by.value;
var at = /@/;
var at2 = /\./;
var found = at.exec(mailstring);
var found2 = at2.exec(mailstring);
if((form.Nome.value == "")||(mailstring == "")){
alert("il nome e la email sono campi obbligatori!!")
return false
}
if((!found)||(!found2)){
alert("campo email non valido!!")
return false
}
else{
return true
}
}