RFC2821 States
452 Requested action not taken: insufficient system storage
This should not (and cannot) be changed within SmarterMail. Doing so would break RFC and could cause unexpected behavior with clients and servers. This response code is for "Requested action not taken" this should be understood by the sender as the message could not be delivered.
Matt Petty
Senior Software Developer
SmarterTools Inc.
www.smartertools.com