Doesn't work with LAGG interface?

[a9tm]

Hi, I'd like to use netmap-fwd with LAGG interface but it won't work.

# ifconfig em0
em0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	options=4219b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,TSO4,WOL_MAGIC,VLAN_HWTSO>
	ether 00:25:90:6a:0f:f4
	inet 10.0.30.105 netmask 0xffffff00 broadcast 10.0.30.255 
	nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
	media: Ethernet autoselect (1000baseT <full-duplex>)
	status: active

# ifconfig lagg0
lagg0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	options=6403bb<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM,TSO4,TSO6,VLAN_HWTSO,RXCSUM_IPV6,TXCSUM_IPV6>
	ether 0c:c4:7a:57:3a:30
	inet 192.168.200.2 netmask 0xffffff00 broadcast 192.168.200.255 
	nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
	media: Ethernet autoselect
	status: no carrier
	groups: lagg 
	laggproto loadbalance lagghash l2,l3,l4
	laggport: igb0 flags=0<>
	laggport: igb1 flags=0<>
	laggport: igb2 flags=0<>
	laggport: igb3 flags=0<>

# netmap-fwd -f /usr/local/etc/netmap-fwd.conf em0 lagg0 
em0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	options=4219b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,TSO4,WOL_MAGIC,VLAN_HWTSO>
	ether: 00:25:90:6a:0f:f4
	inet 10.0.30.105 netmask 255.255.255.0 broadcast 10.0.30.255
disabling rxcsum, txcsum, tso4 on physical interface.
switching interface em0 to netmap mode.
lagg0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	options=6403bb<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM,TSO4,TSO6,VLAN_HWTSO,RXCSUM_IPV6,TXCSUM_IPV6>
	ether: 0c:c4:7a:57:3a:30
	inet 192.168.200.2 netmask 255.255.255.0 broadcast 192.168.200.255
disabling rxcsum, txcsum, tso4, tso6 on physical interface.
ioctl: Invalid argument
cannot open interface: lagg0
ioctl: Invalid argument