Pajes in a J2EE Setting
Java 2 Enterprise Edition (J2EE) defines a standard Java architecture for applications. The standard encourages portability and reuse of developed components and support for distributed deployment among other benefits.
  J2EE Architecture Overview
J2EE encompasses a lot of technologies and components but the following diagram from a Sun Microsystems whitepaper shows the basic structure of a J2EE application server environment.
Enterprise JavaBeans are expected to be used for the provision of business services and integration of enterprise resources (typically but not always databases). The role of JSP is in the provision of a dynamic user interface to these services.
Pajes in a J2EE Environment
The role of Pajes in a J2EE environment is precisely that of JavaServer Pages (JSP) in the above diagram. Pajes provides components which can respond to user requests from a web browser and prepare dynamic HTML/Javascript pages in response. Pajes integrates into a J2EE environment precisely as JSP does and not surprisingly the diagram is very similar.
Pajes can be used in an open source environment or with one of the commercially available J2EE environments (feedback on Pajes in your particular environment would be very much appreciated).
pajes and skinning lightweight servlet