on FreeBSD all vm.memory.size* items get ZBX_NOTSUPPORTED

[root@zabbix-m01 /usr/local/sbin]# zabbix_agentd -t vm.memory.size[total]
vm.memory.size[total]                         [m|ZBX_NOTSUPPORTED]
[root@zabbix-m01 /usr/local/sbin]# zabbix_agentd -t vm.memory.size[active]
vm.memory.size[active]                        [m|ZBX_NOTSUPPORTED]
[root@zabbix-m01 /usr/local/sbin]# zabbix_agentd -t vm.memory.size[used]
[root@zabbix-m01 /usr/local/sbin]# zabbix_agentd -t vm.memory.size[free]
vm.memory.size[free]                          [m|ZBX_NOTSUPPORTED]