[horde] Debug CalDAV and iCalendar(apple calendar)

[김 덕곤]

I have a problem with kronolith calendar.

I use three programs to synchronize my schedule.

1. OS X Calendar.
2. iOS Calendar.
3. Thunderbird sunbird? ( what was the name? )

with Apple programs, I uses CalDAV Account URL ( 
https://.../horde/rpc.php/principals/account_name )
with Thunderbird, I use Calendar's URL ( 
https://.../horde/rpc.php/calendars/... )

In all three program, a schedule can be registered, and I can see the 
schedule on the web(horde).

But, Apple programs does NOT show ALL the events.
( I can not figure out which is missing. and which is showing. )

So, I know it may not be the problem of horde,
but Can anyone tell me how to figure out or debug Calendar programs?