I just set up a git repo for serverwide event.
first update your local repo :
gut pull
then pull serverwide event :
git pull git://github.com/jolan/mangos.git serverwide
then apply sql patches in sql/updates/serverwide_event/
see sql/updates/serverwide_event/readme.txt for DB structure, there is no content sql included so you start with no serverwide event at all but you can test the demo sql from the first post.
the branch dosn't appear on mangos's network graph, that's strange, does someone know why ? [edit] never-mind, github had to refresh it
note : in struct GameEventData (GameEvent.h L54) new variables are not initialized, this is potentially a problem that need analysis