I had a chance to take a look at the new 4.0 version of Jahia and I must say that I am very impressed. As 100% Java solution, it’s a competitive alternative to SharePoint.
Jahia is not quite Open Source however, you do get the source code, but the license model is “Jahia Collaborative Source License (JCSL)”, which roughly means that you can either pay for the license in dollars or pay with code contributions to the project. Certainly an interesting model that is similar to Sun Collaborative Source License (SCSL).
Some of the other interesting facets to Jahia are the stack of Java Open Source Projects that the default install includes. Like for example Tomcat, Slide WebDAV, the Lucerne Search Engine, Struts, OpenLDAP, and HSQL Database Engine.
As far a features go, it definitely crosses the line between CMS and Portal, by integrating rich CMS functionality with workflow and versioning as well as document management (check-in/check-out) with WebDAV access. This is all on top of a highly-configurable “portlet-based” interface framework.