AOL Bounce Error "Improperly formated From Field" 554 RLY:FA

Exchange 5.5 SP4
WinNT SP6a

This setup has been working fine for years. Now suddenly I am getting bounced email from AOL with this message:

554 RLY:FA http://postmaster.info.aol.com/errors/554rlyfa.html 

Following that link the page says the following:

EXPLANATION:

All or part of the from address contained in your message is missing or improperly formatted.

SOLUTION:

Please correct the message "From: address" sent in your SMTP transaction. The from address is typically formatted as myEmailHere@my-Domain.com. You may need to contact your ISP or server administrator for additional assistance.

For additional troubleshooting, reference the manual telnet directions. ***The message From: address is included after the DATA command. ***

(The astrix above are mine for emphasis.)

I go through the telnet commands as AOL suggests on another page and it works fine as shown below:

220-rly-ya01.mx.aol.com ESMTP mail_relay_in-ya1.9; Wed, 08 Sep 2004 22:40:37 -04
00
220-America Online (AOL) and its affiliated companies do not
220-     authorize the use of its proprietary computers and computer
220-     networks to accept, transmit, or distribute unsolicited bulk
220-     e-mail sent from the internet.  Effective immediately:  AOL
220-     may no longer accept connections from IP addresses which
220      have no reverse-DNS (PTR record) assigned.
helo mydomain.net
250 rly-ya01.mx.aol.com OK
mail from:<myemail@mydomain.net>
250 OK
rcpt to:<somebody@aol.com>
250 OK
Data
354 START MAIL INPUT, END WITH "." ON A LINE BY ITSELF
from: <myemail@mydomain.net>
This is a test.
.
250 OK

Yes, the <> are required.  So that works well. As I highligted above with the astrix I did notice that AOL specifically asks that you put a "from: myemail@mydomain.net" after the DATA command. When I DO NOT I get the following:

220-rly-xg05.mx.aol.com ESMTP mail_relay_in-xg5.5; Wed, 08 Sep 2004 22:54:55 -04
00
220-America Online (AOL) and its affiliated companies do not
220-     authorize the use of its proprietary computers and computer
220-     networks to accept, transmit, or distribute unsolicited bulk
220-     e-mail sent from the internet.  Effective immediately:  AOL
220-     may no longer accept connections from IP addresses which
220      have no reverse-DNS (PTR record) assigned.
helo mydomain.net
250 rly-xg05.mx.aol.com OK
mail from:<myemail@mydomain.net>
250 OK
rcpt to:<somebody@aol.com>
250 OK
Data
354 START MAIL INPUT, END WITH "." ON A LINE BY ITSELF
This is a test.
.
554-: (RLY:FA) http://postmaster.info.aol.com/errors/554rlyfa.html
554 TRANSACTION FAILED

This is the error that is showing up in the bounced back email.  So AOL is requiring the "from: myemail@mydomain.net" after the DATA line. Is there some reason that this is not done when the email is sent via my exchange server? Is there some setting in Exchange to do this?

Thanks for your help.

David