DECLARE
  mailconn   UTL_SMTP.connection;
  mailhost   VARCHAR2 (10)       := '_enter_your_mail_server_here_';
BEGIN
  mailconn := UTL_SMTP.open_connection (mailhost, 25, 10); -- third parameter is timeout.
  UTL_SMTP.helo (mailconn, mailhost);
  UTL_SMTP.mail (mailconn, 'sender@email.address');
  UTL_SMTP.rcpt (mailconn, '_enter_your_email_address_');
  UTL_SMTP.DATA (mailconn, 'some thing............'); -- don't forget the connection (first parameter)
  UTL_SMTP.quit (mailconn);
END;