Keep multiple calendars in sync (iCal, all on same mac)

[Cantello]

Hey all,

I'd like to keep two calendars on the same mac synched. If I change things in one, the other should reflect these changes. Not necessarily instantly but in intervals.

Does any of you know of a solution? Maybe some kind of folder mirroring for both calendar folders?

The background is that I'd like to sync my iCal calendar to Google Calendar and additionally to my mobile phone. However, events created on the phone cannot by synched by iSync to the calendar that is synched to Google (via CalDAV), only to iCal's main calendar, which is not the same as the one synched to Google.

Phew, complicated...

Any hints?

Thanks,
Helge.