553 Requested action not taken

[briansdell]

Help! we recently started using a service called Postini for filter our email for spam. One of the services that they provide is notification messages. These messages are sent from postini to each user with information about checking messages to updating passwords. For some reason these messages are erroring out to the administrators email box. In testing we can telnet to the server and SMTP responds correctly until we use an email address of someone with a valid address on the domain then it fails with the error show below.

553 Requested action not taken: mailbox name not allowed or chunk too large
(in reply to MAIL FROM command)

I am also including the Telnet test so you can see what is happening.

[exprod8gw] $ telnet 64.1.193.214 25
Trying 64.1.193.214...
Connected to 64.1.193.214.
Escape character is '^]'.
220 SMTP service ready
helo domain.com
250 Requested mail action okay, completed
mail from:<brians@bensonmcl.com>
553 Requested action not taken: mailbox name not allowed or chunk too large
quit
221 SMTP server closing transmission channel
Connection closed by foreign host.
[exprod8gw] $ telnet 64.1.193.214 25
Trying 64.1.193.214...
Connected to 64.1.193.214.
Escape character is '^]'.
220 SMTP service ready
helo domain.com
250 Requested mail action okay, completed
mail from:<ccji@postini.com>
250 Requested mail action okay, completed
quit
221 SMTP server closing transmission channel
Connection closed by foreign host.
[exprod8gw] $ telnet 64.1.193.214 25
Trying 64.1.193.214...
Connected to 64.1.193.214.
Escape character is '^]'.
220 SMTP service ready
helo domain.com
250 Requested mail action okay, completed
mail from:<>
250 Requested mail action okay, completed
quit
221 SMTP server closing transmission channel
Connection closed by foreign host.
[exprod8gw] $ telnet 64.1.193.214 25
Trying 64.1.193.214...
Connected to 64.1.193.214.
Escape character is '^]'.
220 SMTP service ready
mail from:<trishac@bensonmcl.com>
553 Requested action not taken: mailbox name not allowed or chunk too large
quit
221 SMTP server closing transmission channel
Connection closed by foreign host.

Any information that could resolve this issue would be helpful

Thanks
Brian