You get an error from a virtual server configured as proxy for e.g. tomcat or glassfish
This is due to your configuration of your proxy. On debian you find a default configuration which will deny all clients.
This is a proxy.conf configuration, I changed the "Deny from all" into "Allow from all" and now everything works. I have a glassfish server as a virtual host on 8080 running behind apache.
#turning ProxyRequests on and allowing proxying from all may allow
#spammers to use your proxy to send email.
Allow from all
# Enable/disable the handling of HTTP/1.1 "Via:" headers.
# ("Full" adds the server version; "Block" removes all outgoing Via: headers)
# Set to one of: Off | On | Full | Block
About the Author
Wim Peeters is electronics engineer with an additional master in IT and over 30 years of experience including time spent in support, development, consulting, training and database administration. Wim has worked with SQL Server since version 6.5. He has developed in C/C++, Java and C# on Windows and Linux in different European countries and different European languages. He writes knowledge base articles to solve IT problems and publishes them on the Lubby Knowledge Platform where he is one of the most important contributors and the main developer.