Calendars other than gmail or outlook?

Hi, I posted this (more or less) on the 82xx forum and got no response-- I'm hoping someone here can help me!

Hi! I just got a 8230 flip. I am trying to find a calender that I can synch between my PC and bb other than gmail/yahoo or outlook.

I have tried using the Outlook Calendar in the past at work but I just don't like it. One the other hand, I suspect web-based calenders (like what Yahoo provides) are not secure -- I need my meetings to remain confidential for professional reasons. I have been using Thunderbird at work with the calender feature but I think that Mozilla and Blackberry are not speaking at the present time.

Does anyone have an alternate program that would sync Blackberry calender? Thanks!

bump, I have a user that is facing this exact issue and am investigating options for him.