source: http://www.securityfocus.com/bid/3749/info

DeleGate is a proxy server which runs on Linux , Unix, Microsoft Windows and OS/2 platforms. It is capable of translating a number of protocols(HTTP, FTP, NNTP, POP, Telnet, etc.) between client and server.

DeleGate is prone to cross-site scripting attacks. HTML tags are not filtered from links to error pages. As a result, it is possible for an attacker to insert malicious script code into a link to a site running DeleGate. When a web user clicks the link an error page will be displayed and the script code will be executed on the web user in the context of the site running DeleGate.

Such an attack may be used to steal a legitimate user's cookie-based authentication credentials. 

http://IP_Address_of_DeleGate/<script>alert("aaa");</script>