I made an important change to GO, I moved the configuration options to a new file. Group-Office.php is now static and the config is in local/config.php. All local stuff will go into that dir so it's possible to seperate source from local stuff with symlinks.
Running install.php will automatically create the new config.php but beware that the new static Group-Office.php is in CVS now and will overwrite your local copy when you checkout.
But if you back it up and replace it with your old one and then run install.php it will keep your config.