Well as great as the iphone is, the software is laggign a fair way behind and calendar syncign is one example.
After many hours, here’s a solution I found to sync multiple calendars across different computers, with anyone being able to edit the calendars, and see them on your iphone as well.
1. SET UP A MASTER CALENDAR Your master calendar needs to be in google (not on your mac). So create a google calendar here. Because I wanted to share it among my colleagues and have them edit it, I created a special goggle account just for this calendar. After you create the calendar you can export your existing events from your mac as an ics file and import them into google calendar.
2. SYNC IT TO ICAL Download a little google application called ‘Calaboration’ from here which will add your google calendar to ical. You will need to enter your google id and password. You will need to run Calaboration on any mac you want to access the google calendar on.
3. SYNC IT TO IPHONE Your iphone can sync to google calendar via the ClaDAV option on the iphone. Google is basically being an exchange server that your phone syncs to. The instructions are here.
I have a newer post about this here.