Ah, I love fixing bugs. Well OpenFlock is getting really close to its first public alpha. I've got the server pretty much working the way it is supposed to, although it is missing a number of advanced features (like authentication, doh!) and I finally got the GCTP client library almost there. Currently, it is still more of a toolkit than a real set of client programs, but I have created a simple 10 line client that connects to the server and creates appointments, checks schedules, etc.
Just a little further to go to actually have a client that is usable - and then it is only a few steps from there to having a web-based client...
Then all I have to do is write up a formal description of the GCTP protocol so that others can create fully interoperable group calendaring clients and servers too.