I was trying to print out user credentials in my sidebar, so i first tried to var_dump some of the global variables.
(http://www.zenphoto.org/news/zenphotos-global-variables)

But surprisingly this did not work.
E.g. $_zp_admin_users, $_zp_current_admin (after admin logon) are not present and var_dump prints out NULL.

Thanks, apparently we forgot to update that article… The current admin is in $_zp_current_admin_obj and the full user set in $_zp_authority.

Thank You for the reply!...

Found it out, too, by eating myself through the core-files ^^