RE: abused webmail

[Paul Hutchings <paul.hutchings@xxxxxxxxxx>]

I know this is real easy to say but wouldn't you better off finding and
fixing the exploit rather than dealing with it downstream?

regards,
Paul
-----Original Message-----
From: owner-postfix-users@xxxxxxxxxxx
[mailto:owner-postfix-users@xxxxxxxxxxx]On Behalf Of columbo
Sent: Wednesday, September 01, 2004 4:59 PM
To: postfix-users@xxxxxxxxxxx
Subject: abused webmail


Hello,

I would like to find some solution against spammers, who are abusing our
webmail, based on Iplanet Messagging server. (or how do the SUN  call it
now:)
They (spammers) probably use some simple POSTing script through which they
cram thousands of messages.
There are postfix MTA servers in the frontend network and messages from
backended webmail are forwarded to them. Presently we are not able to stop
them right on the backend, we need to cut them down on the outgoing
postfixes.  So what we need is to limit number of messages in for example
five minutes, coming from one concrete address (webmail backend) and from
one concrete user (From:webmailuser@xxxxxxx) together. 
Any idea how to handle this? 

Thank you for any help.
Mesijeur Grygar