[MailScanner]
DefaultPopServer=pop.mail.yahoo.it
DefaultSmtpServer=smtp.mail.yahoo.it
ShowTrayIcon=1
UseDefaultSmtp=0
AutoSetProtection=1
PopListen=127.0.0.1:110
SmtpListen=127.0.0.1:25
ImapListen=127.0.0.1:143
StartSMTP=0

I change in this way the avast4.ini is right?
thanks for the help bye!!

or in this way?
[MailScanner]
StartSMTP=0