X11 forwarding with ssh

I have installed SSH Secure Shell Tru64 UNIX 3.2.0 on both systems 
(server and client) and would like to forward the X11 over the ssh 
connection.
After connecting I start a X application but it fails with:

X11 connection rejected because of wrong authentication.
X connection to zuvrobot.zuvrz.unizh.ch:10.0 broken (explicit kill or 
server shutdown).

I have checked that the xauthpath is correct and the ForwardX11 is set 
to 'yes' on the client and on the server configuration files.

Thanks for any help.


Best regards

Ulrich

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  | Ulrich Bernhard                                           |
  | Informatikdienste      Tel: (+41-44) 635 67 73            |
  | Universitaet Zuerich   Fax: (+41-44) 635 45 05            |
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  | Switzerland                                               |
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