Problem with some URLs

I got problems with some URLs hen I go through Squid.

For example the following:

http://setiathome.ssl.berkeley.edu/cgi-bin/cgi?name=ludolph%40uni-bielefeld.
de&cmd=user_stats

results to:

----------------------------------------------------------------------------

----
While trying to retrieve the URL:
http://setiathome.ssl.berkeley.edu/cgi-bin/cgi?
The following error was encountered:
     Unable to determine IP address from host name for
setiathome.ssl.berkeley.edu
The dnsserver returned:
     DNS Domain 'setiathome.ssl.berkeley.edu' is invalid: Host not found
(authoritative).
This means that:
 The cache was not able to resolve the hostname presented in the URL.
 Check if the address is correct.
----------------------------------------------------------------------------
-----
This does not happen, wehen I use direct connection.
Thanks fpr any help
Patrick