[Zope] Server not found or DNS error

Hello All, A problem appeared recently after some system reconfiguration (now Debian 3.0, Zope 2.6.2, Postgresql 7.2.1 at Celeron-366/512 Mb RAM, Apache is not used)- opening any link in a Zope application (mostly in OIO, www.txoutcome.org) unpredictable causes "Server not found..." error and if through Squid - "Zero sized reply" or "Permission denied". Pressing "Refresh" 4-10-12 times still opens the link. Any hint how to fix this? -- Best regards, Alexander N. Chelnokov Ural Scientific Research Institute of Traumatology and Orthopaedics 7, Bankovsky str. Ekaterinburg 620014 Russia