Java EE (Java Enterprise Edition) General Discussion

I am getting a very strange, and intermittent error whilst using Sun's SMTP mail package (com.sun.mail.smtp).

I am using the SMTPTransport object to send an email (of type com.sun.mail.smtp.SMTPMessage), and am getting the following exception:

javax.mail.SendFailedException: 452 4.2.2 Mailbox full

... This seems to be an exception preceeding (possibly causing) a javax.mail.SendFailedException: Invalid Addresses exception. It is "possible" that I do have an invalid address, however it is unlikely. What concerns me more is this "Mailbox full" error.

Has anyone seen this or knows what it means?

Thanks.

Full Exception Trace
------------------------
javax.mail.SendFailedException: Invalid Addresses;
nested exception is:
javax.mail.SendFailedException: 452 4.2.2 Mailbox full

Code snip that sends the email
---------------------------------

transport = (SMTPTransport)session.getTransport("smtp");
transport.connect(server.getNetworkAddress().getHostAddress(), server.getAccessAccountName(), server.getAccessPassword());
message.saveChanges(); // don't forget this

// By default, we just use the message recipients
if(recipients == null) {
recipients = message.getAllRecipients();
}

transport.sendMessage(message, recipients);