vlan interface does not repond on untagged packets

Hi,

i am creating and testing vlan using these commands,

*ifconfig arge0 192.168.100.10 netmask 255.255.255.0*
*
*
*ifconfig vlan4 create*
*ifconfig vlan4 vlandev arge0 vlan 4*
*ifconfig vlan4 192.168.1.10 netmask 255.255.255.0*

here arge0 is the default interface of my ethernet device,

now i want to access vlan4 interface from an other pc which has linux and
is dirctly connected to my freebsd machine, now if i try to ping linux
machine it will send tagged packets but linux does not recogniz it and
leave it, and similarly when i try to ping linux machine to vlan4 interface
on freebsd, linux send untagged packets so vlan4 does not response to it.

I want that my vlan4 interface could able to recongnize untagged packets
and could respond to it

Thanks