Jetspeed is an Open Portal Platform, written entirely in open source under the Apache license in Java and XML.
Jetspeed allows to build your own custom portal based on jetspeed or to use base jetspeed.
You download out-box jetspeed from download, It comes with Jetspeed portal server and j2-admin(Jetspeed administrative portlet application)
Jetspeed out-of-box comes with tomcat5, but it can be deployed to any application server. Jetspeed can be deployed to any application server.
Jetspeed 2 is fully JSR-286 based portlet container.