restrict access to server to a non-resolved address

[Dieter Blaas]

Hi,  
   I already posted a similar question some time ago but the 
answers showed me that I was misunderstood. So, I am trying 
again:

I want to restrict, on the server side, access to a single user. 
This user has a dynamic IP, which, by using dyndn.org, 
translates into xyz.dyndns.org. I know how to restict assess to 
a normal IP address but if I enter (in the server's setup dialog) 
an address like xyz.dyndns.org (instead of e.g. 
120.231.139.12) it does not accept it. Is there any way of doing 
this?
   To be even more clear: I want that user xyz.dynds.org can 
access the server regardless which real IP it has at a given 
time. Maybe the free version cannot but presonal or enterprise 
can?
Thanks a lot for hints, Dieter 
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Dieter Blaas,
Max F. Perutz Laboratories
Medical University of Vienna, 
Inst. Med. Biochem., Vienna Biocenter (VBC), 
Dr. Bohr Gasse 9/3, 
A-1030 Vienna, Austria, 
Tel: 0043 1 4277 61630, 
Fax: 0043 1 4277 9616, 
e-mail: dieter.blaas "at" meduniwien.ac.at
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