CFMail Behavior in CF9 -- Invalid Email Accounts

Hello,

We recently switched from ColdFusion 7 to ColdFusion 9. The environment is as follows:

ColdFusion 9 Standard version 9.0.1,274733

Windows Server 2008 R2

Apache 2.2

We send outgoing e-mails using our local campus SMTP server. In the past, with CF7, when an account did not exist on the smtp server the mail would go into the Undeliverable folder. This worked out great, because we could scan this folder and find e-mails that were not delivered due to expired e-mail addresses.

In CF9, this behavior has changed. The mail is now "sent successfully" according to the logs, and not moved into the undeliverable folder. The problem with this is that the mail has NOT been sent successfully! The SMTP server rejects the message at the sending stage, and CF9 just ignores this and says the mail was sent successfully. Since the SMTP server rejects it, I do not receive an "undelivered email" message from the server.

We skipped CF8, so I don't know if it behaves this way or not.

Here is a copy of the debug log for an smtp session, illustrating the problem:

MAIL FROM:<me@school.edu>
250 2.1.0 <me@school.edu>... Sender ok
RCPT TO:<thisisnotarealemailaddress@school.edu>
550 5.1.1 <thisisnotarealemailaddress@school.edu>... User unknown
DEBUG SMTP: Invalid Addresses
DEBUG SMTP:   thisisnotarealemailaddress@ucdavis.edu
DEBUG SMTP: Sending failed because of invalid destination addresses
RSET
250 2.0.0 Reset state
javax.mail.SendFailedException: Invalid Addresses;
  nested exception is:
    com.sun.mail.smtp.SMTPAddressFailedException: 550 5.1.1 <thisisnotarealemailaddress@school.edu>... User unknown

    at com.sun.mail.smtp.SMTPTransport.rcptTo(SMTPTransport.java:1446)
    at com.sun.mail.smtp.SMTPTransport.sendMessage(SMTPTransport.java:736)
    at coldfusion.mail.MailSpooler.deliver(MailSpooler.java:1006)
    at coldfusion.mail.MailSpooler.sendMail(MailSpooler.java:905)
    at coldfusion.mail.MailSpooler.deliverStandard(MailSpooler.java:1310)
    at coldfusion.mail.MailSpooler.run(MailSpooler.java:1275)
    at coldfusion.scheduling.ThreadPool.run(ThreadPool.java:201)
    at coldfusion.scheduling.WorkerThread.run(WorkerThread.java:71)
Caused by: com.sun.mail.smtp.SMTPAddressFailedException: 550 5.1.1 <thisisnotarealemailaddress@school.edu>... User unknown

    at com.sun.mail.smtp.SMTPTransport.rcptTo(SMTPTransport.java:1297)
    ... 7 more
QUIT
221 2.0.0 smtp2.school.edu closing connection
05/17 08:59:00 Information [scheduler-2] - Mail: 'This is a test.' From:'me@school.edu' To:'thisisnotarealemailaddress@school.edu' was successfully sent using smtp.school.edu

Any ideas on how to correct this behavior?

Thanks!