VLAN Use on Home UTM

Greetings Folks,

  I recently delved into adding two layer-2 switches to my home network getting rid of my un-managed units.  I am trying to setup separate VLAN's for private vs guest networks.  

  Can the UTM handle multiple VLAN's on one physical NIC?  

  I modified my Internal interface to be of type "Ethernet VLAN" and set the VLAN to 1 for initial setup.  I then added two additional interfaces on that same NIC of type "Ethernet VLAN".  I setup Private on VLAN 10 and Public on VLAN 20.  192.168.10.1/24 and 192.168.20.1/24 respectively.

  In essence all on eth0, I have:

VLAN 1  -  192.168.254.1/24

VLAN 10  -  192.168.10.1/24

VLAN 20  -  192.168.20.1/24

  My layer-2 switch is connected to the UTM on port 1, and set as a trunk port allowing VLAN 1,10,20 to it.

  When I add ports to VLAN 10 or 20, I am getting a fair amount of packet-loss when pinging those Interfaces from machines plugged into these tagged ports.  I have tried to set the PVID of the switchport to the matching VLAN and that isn't helping the problem either.

  So in addition to the initial question above, I'm trying to diagnose if this is a misconfiguration of my switch, or if I am setting up the UTM incorrectly.

  Any thoughts or comments would be greatly appreciated! :)