Tiki and Cypht webmail interoperability started with Tiki20
. Major work has been done since that time in Cypht, and in Tiki 21, 22, 23. Work is ongoing, so it's recommended to run the latest 23.x from Git/SVN or Daily Build
. Most enhancements and many fixes will not be backported to Tiki21
LTS as there are lots of changes.