Upgrade from ZCS5 to 6 oddness in CalDAV iPhone sync

[carnold]

I have the same problem on 3.1.3. CalDAV use to work, then i had to restore the iphone b/c of charging issues and general slowness of iphone. Now i can not get any of my existing "events" from the zimbra server to show up on the iphone. Anyone figured this out yet?

[mfehr]

I have the same problem with the slight difference that it once worked before:

I run Zimbra 5.0.14 on Ubuntu server
I have the following CalDAV clients:
- iCal on Mac OS X 10.6.3
- Mozilla Sunbird 0.9 on Windows XP
- Zimbra web client ;-)
- iPhone 3.1.3

My Zimbra account has the following calendars:
- my own calendar
- subscription to a shared Zimbra calendar on the same server
- 4 iCal subscriptions

All clients including the iPhone worked using a CalDAV connection. I was able to create entries for both clendar entries on any of these clients and saw the change on the others.

Since a few days, I have a changed behavior on my iPhone:
- I do no more see any updates
- I can create new entries from the iPhone

I deleted and recreated the account on the iPhone. What I see is that all my iCal subscriptions are showing up again. All Zimbra calendars however, only appear in the overview with the correct colors but no entry is visible on the iPhone.

It seems that the CalDAV connection works fine. This is also what I see in mailbox.log. Nothing points me to an error.

I also tested with a second iPhone (3.1.2) using the same shared calendar. This iPhone works without any problem. So my assumption is that this problem must be related to the iPhone. My iPhone is on release 3.1.3.

Any hints how I can have a more detailed trace on Zimbra to see the communication between Zimbra and the iPhone or how to fix it on the iPhone?

[Klug]

Here in France, we have noticed that some carriers (at SFR for several months and now Orange too) are "filtering" CalDAV traffic.

I don't know where/how it's done (I guess their transparent proxy is doing the job) and I have no clue why it's done... But it"s done.

Are you tests done using WiFi or 2G/3G ?

[mfehr]

As I run my Zimbra server on my own hardware, I can access Zimbra over WLAN and the Internet. For my test purpose, I use the WLAN connection.

[mickier]

One of my users had the same issue, and he figured out a fix (for him):

[set your iphone to only sync the past 3 months]

Thank you thank you!