ICal Feature, Bug, or Configuration Problem?

Question

We have a school calendar running on iCal Server (10.6.4) called "CS Calendars". Each user has one default calendar when the account is created on the local MacBook (10.6.4). Many users have created additional calendars under "CS Calendars" so that they will show up as "busy" if they schedule stuff on the other calendars.
Here's the problem...
A users sends an "invite" to another user. That user accepts the invite. The appointment shows up initially under "(username)'s Calendar" under "CS Calendars". The user now wants to change the appointment to another of their calendars under "CS Calendars". As soon as they select the other calendar an error message pops up saying:
The server responded with an error.
The request for (Name of Invite) in (Name of OTHER Calendar) in account "CS Calendars" failed.
The server responded with
"HTTP/1.1 502 Bad Gateway"
to operation CalDavMoveEntityQueueableOperatioin.
I have googled that error operation and can't find but 6 links on the entire internet that has any reference to it and some of them are duplicates.
Is this a prohibited operation by CalDAV? (The user SWEARS to me that she was able to do this last year - we have had 4 iterations of 10.6 since then) Is this a bug in CalDAV? or (more likely) Do I not have iCal Server configured correctly OR the client misconfigured?
Thanks for any help.
John Orban
System Administrator
The Country School

Answer 1

Apple Engineering is looking into this issue. Not sure what the problem is but it appears that if you have a user with an iCal acccount created via the "automatic" method this type of behavior occurs. The fact that it was working until recently makes me wonder if a software update broke something?
What has worked so far is to delete the old iCal account. Create a new one but use "CalDAV" as "Account Type". Then enter port # 8443 and check the SSL box (we have both SSL and non-SSL access to our calendar). Create the account.
Unfortunately, as soon as you do another error message is thrown stating that the username or password is incorrect. When you go back to account settings, the Password Field is BLANK. Re-entering the password seems to then fix the issue.
I didn't pick up on the problem because I only have one calendar and don't move appointments around like my users do. I'll report what Tech Support finds out.