Hi Ken,
Basically, the shared calendar is working fine in Thunderbird, where I
can specify the exact URL. But I can't make it work on iPhone as it only
takes the server and later resolves the exact URL via
/.well-known/caldav which points to the personal calendar for the same
user. Though, if
Shared seen in 2.4 and below was done by storing the seen information in
a global database. In 2.5 and above, it's stored in the cyrus.index (if
shared seen is enabled, it duplicates the owner's seen information).
It may be that the upgrade path is broken for shared seen, I'm not sure
how well it
