Here is a list of some of the places I've found the plugin mentioned. If you would like to say something (nice!) about the plugin then please email me, my address is channingwalton (the at thing) mac.com.
Yoxos is a collection of plugins that includes the Wiki editor. They say: Yoxos delivers Eclipse plus many of the most popular open-source plugins - on CD or as a download - ready for deployment.
Eclipse: Building Commercial Quality Plug-ins
Jazzing up Eclipse with collaborative tools
The plugin is referenced in this Paper :Collaboration is an integral part of software development, occurring through tools inside and outside the IDE. This paper presents an overview of the Jazz project, which seeks to integrate collaborative capabilities into the Eclipse IDE, enabling small teams of software developers to work together more productively.