Sun GlassFish Enterprise Server v2.1.1 Upgrade Guide

Implicit URL Rewriting

Application Server 6.x supported implicit URL rewriting, in which the web connector plugin parsed the HTML stream being sent to the browser and appended session IDs to attributes such as href= and frame=. In Application Server 7,8, and Enterprise Server, this feature is not available. You need to review your applications and use encodeURL and encodeRedirectURL on every URL that the applications present to clients (such as mobile phones) that do not support cookies.