svn checkout https://wbwiki.svn.sourceforge.net/svnroot/wbwiki
Copy everything under wbwiki/trunk/repo to your maven repository (for example c:/maven-repo, depending on what you wrote in maven/conf/settings.xml)
NOTE: this is ugly, but the simplest solution I could find. I first tried to set up an internal repository at http://wbwiki.sourceforge.net/repo, but there were some problems. The stuff we use that isn't in the default repo is:
If everything is fine you should now see a working, running Whiteboard Wiki!
To simplify life, the WbWiki project includes Eclipse project files. So you should just be able to import the project. The project does use a couple of plugins though.
If everything is fine you should now see a running WbWiki (using GWT development shell).
mvn idea:idea
... and hope for the best. Haven't tried it myself.