if which dzhandle >/dev/null; then
    case "$1" in upgrade|remove)
	# upgrade:
	#  - register instances, in which extension is upgraded
	#  - remove extension from instances
	# remove:
	#  - register instances, in which extension is removed, needed
	#    for recovery in postinst abort-remove
	#  - remove extension from instances
	#  - maybe fail if extension installed in instance with addon policy
	#    all and addon-mode linked or tree-linked

	dzhandle prerm-extension -m "$*" #DZ-DIR#
    esac
fi
