Delegation workaround for iCal 3 (OS X 10.5)

[prebenu]

Hi forum,

We upgraded to 6.0.2 this weekend, and on top of the "family mailboxes" bug, we are having some issues on our 10.5 based Macs. More specifically iCal 3.

Without "Enable delegation for Apple iCal CalDAV client" checked, I receive the following error in iCal:

"The calendar https://mail.mydomain.dk/principals/...e@mydomain.dk/ was not found on the server. Make sure the URL is correct."

Happenes on both 10.5 and 10.6.

On 10.6:
When "Enable delegation for Apple iCal CalDAV client" is enabled, I get to see my delegates under Accounts -> Delegation. I can check the calendars I want to see. All good.

On 10.5:
When "Enable delegation for Apple iCal CalDAV client" is enabled, I do not see any delegates under Accounts -> Delegation. That means that I can only see my own calendar, which is pretty critical to us. According to Bug 21489 – CalDAV: Add support for calendar delegation the bug has only been fixed for iCal 4.0, but will not be fixed for 3.x according to Comment #51.

Is there any workaround for iCal 3 or is the only way of solving the problem upgrading to Snow Leopard?

Kind regards,
Preben