Hello, I'm looking at the POPMail hybrid product and converting it to ZPT. In the meantime, I'm a bit puzzled with the relation between the attributes of a Python class and the attributes of a PropertySheet of a ZClass. The zope book (extending zope) is too short on this. Namely I've in a Python file (POP.py): class POPMailAccountBase: def __init__(self, user='noname', passwd='nopass', server='noserver'): self.user = user self.passwd = passwd self.server = server and a PropertySheet (server_authentication) of the ZClass (POPMailAccount): server: string user: string passwd: string Can someone explain (or point to some doc) how is one updated from the other? For instance, when I create an instance of a POPMailAccount, the Edit screen of the PropertySheet immediately appears with the values of the Python class attributes (like above). If I modify these values in the ZMI screen, I _suppose_ the attributes of the Python class get modified. I'm not sure this is actually happening, because I had to restart Zope and only then did the product seem to work (by retrieving the messages from the server which it had no found before). Thanks, Fernando