High availability and VLAN

Hi,

i installed UTM9 on my home network. Evrything is fine, but my question is, i'm using a cisco switch on LAN-side, and i have installed two NIC's one for outside and the second for inside/DMZ/and so on. Is it possiple to use a VLAN-based interface as sync NIC for High availability or do i have to use a third NIC for syncing?

VLAN-based syncing would be very fine!

Thanks in advance,
regards
Herbert