- PHPSESSID is set by PHP, not by Tiki.
You can change the name of PHPSESSID in tiki-admin.php?page=general#contentadmin_general-2
- PHPSESSIDCV is added by Tiki in
tiki-setup_base.phpas "extra_validation" against session collisions.
- local_tz is for local timezone in case dates need to be displayed in the timezone of the viewer.
That's all I know