redirect / ereject loops

Hello,

While you are talking about loops with "notify mailto", I would like to 
ask you about loops with "redirect". I redirect the mail for my 
university account to uni(_at_)mydomain, which has the following script:
if header :contains "X-Spam-Level" "+++++"
        {
                redirect "me(_at_)mydomain";
                stop;
        }

So, when a spam arrives, the responsibility for the mail is taken and 
the mail is redirected to me(_at_)mydomain(_dot_) In the past me(_at_)mydomain moved 
such mails to INBOX.Spam, but recently I changed the script to
require ["ereject"];

if header :contains "X-Spam-Level" "+++++"
        {
        ereject "Your mail was evaluated as spam and was not delivered.
However you can contact me at +49 721 755345(h) or +49 176 20700494(m).";
        stop;
        }

and ereject does SMTP reject. Such redirecting script is also installed 
for the postmaster(_at_)(_dot_) Now my question is, what happens with the spam 
mail: it entered the system being accepted by uni(_at_)mydomain, but it 
cannot end in a mailbox. At the end it enters the postmaster mailbox, 
bypassing somehow (to be figured out) the spam filter and growing to 
500k. I have uploaded one such message at 
https://mail.aegee.org/~didopalauzov/Automatically%20rejected%20mail.eml .
Is this normal? Any ideas what to do?

        Със здраве,
                Дилян