[Exim] ACL verify response messages

Hi,

I have an ACL on "MAIL FROM" that looks like:

  deny message = AN INVALID FROM ADDRESS WAS USED IN YOUR EMAIL!
       ! verify = sender/defer_ok

This ACL is restricted to just our customers, who are primarily
using Outlook Express to inject messages.

Problem is, the output message comes out as:

    550-Verification failed for <badaddress@???>
    550-The user "badaddress@???" does not exist
    550 AN INVALID FROM ADDRESS WAS USED IN YOUR EMAIL!

But I want it to only have a single line of:

    550 AN INVALID FROM ADDRESS WAS USED IN YOUR EMAIL!

Is there any way to get this extra text to go away? I thought that
the message= qualifier would override any normal output.

Why am I concerned about this?

Because Outlook Express won't show the error to the user unless there
is *exactly* one 5xx line. If multiple lines are sent, Outlook gives
a very generic error instead of showing the response text.

Is this a feature or unintended behavior?

Thanks!

--
Dean Brooks
dean@???