Hi Patrick,
That feature was developed at the time to enable iPhones to receive basic contact information from a SOGo addressbook, when it was not CardDAV-capable. We did indeed develop it to return only a few useful and main properties but it does not mean it cannot be enhanced... So it's not a bug but rather a limitation of the current implementation.
Cheers, Wolfgang -- [email protected] https://inverse.ca/sogo/lists
