source: http://www.securityfocus.com/bid/8869/info

It has been reported that PSCS VPOP3 Email Server may be prone to a cross-site scripting vulnerability that may allow a remote attacker to embed malicious HTML and script code in a link. The issue is reported to be present in the WebAdmin utility of the software because of improper sanitization of user-supplied data that will be displayed by the utility.

Successful exploitation of this attack may allow an attacker to steal cookie-based authentication information that could be used to launch further attacks.

PSCS VPOP3 versions 2.0.0e and 2.0.0f have been reported to be prone to this vulnerability, however other versions may be affected as well. 

index.html?redirect=admin/index.html";%0Devil_script;%0D// 