Mail doesn't send - javax.mail.MessagingException: 250

Question

Hello all,
I'm new to JavaMail. I actually started with it last night. I've successfully sent a number of messages, but I randomly get a strange exception for no apparent reason.
If I run the exact same code several times, it will produce this error about every 5 or 6 times:
javax.mail.MessagingException: 250 Requested mail action okay, completed
Does anyone know what might be going on? Thanks in advance for any help you might can give.
Here is the heart of my code:
// Get system properties
Properties props = System.getProperties();
// Setup mail server
props.put("mail.smtp.host", host1);
// Get session
Session session = Session.getDefaultInstance(props, null);
          session.setDebug(true);
// Define message
MimeMessage message = new MimeMessage(session);
// Set the from address
message.setFrom(new InternetAddress(fromAddress));
// Set the to address
message.addRecipient(Message.RecipientType.TO, new InternetAddress(toAddress));
// Set the subject
message.setSubject(subject);
// Set the content
message.setContent(content, "text/html");
// Send message
Transport.send(message);
Below is the debugger output: (certain values have been removed for anonymity's sake)
DEBUG: getProvider() returning javax.mail.Provider[TRANSPORT,smtp,com.sun.mail.smtp.SMTPTransport,Sun Microsystems, Inc]
DEBUG SMTP: useEhlo true, useAuth false
DEBUG: SMTPTransport trying to connect to host "xx.xx.xx.xx", port 25
DEBUG SMTP RCVD: 220 domain.company.com ESMTP MailEnable Service, Version: 1.704-- ready at 01/14/04 14:07:27
DEBUG: SMTPTransport connected to host "xx.xx.xx.xx", port: 25
DEBUG SMTP SENT: EHLO licensing
DEBUG SMTP RCVD: 502
DEBUG SMTP SENT: HELO licensing
DEBUG SMTP RCVD: 250-AUTH LOGIN
250-SIZE 5120000
250-HELP
250 AUTH=LOGIN
DEBUG SMTP: use8bit false
DEBUG SMTP SENT: MAIL FROM:<[email protected]>
DEBUG SMTP RCVD: 250 Requested mail action okay, completed
DEBUG SMTP SENT: RCPT TO:<[email protected]>
DEBUG SMTP RCVD: 250 Requested mail action okay, completed
Verified Addresses
[email protected]
DEBUG SMTP SENT: DATA
DEBUG SMTP RCVD: 250 Requested mail action okay, completed
DEBUG SMTP SENT: QUIT

Answer 1

But I am getting that code thrown as a MessageException; the message never goes through. If you look at the debugging output compared to a message that went through, the DATA transmission commands are screwed up.
Thanks for your input, though. I think I've gotten around this by trying to resend the message. It looks like that when I get this exception the message is never sent. I have a catch that detects this exception and tries to resend up to 3 times.
Thanks,
floosh