Don't know why this phone's stock calendar is flaky as far as syncing goes, but I read about this issue on another site and the recommendation was to use "Business Calendar"to allow all the syncing to actually work. Just make sure you don't have notifications enabled on both calendars at the same time.
Same problem here. I had to disable the Google Calendar
Sync in the Setting-Application option. Now' there is no option to enable it again. I use Business Calendar too, and it would not sync either. Any fix to this problem?
I'd say it's likely the ROM you are using. I run stock, non rooted and the calendar syncs just fine. I use aCalendar for my calendar widget. Evrything is synced, even my FB, and it's always up to date.