Any way to get a vlan to cross a tagged port and a software switch?

[ispcolohost]

Hi all, got some 200E's and have a need for a particular vlan to be visible on both a software switch and an uplink port to the network infrastructure; is that possible?

e.g. vlan 5 is network management, so I have a vlan5_netmgmt interface created tagging vlan 5 on the firewall's uplink to the network core, but I also have a need to plug a couple devices into the firewall's ports that need to be on that vlan as well.  

It seems like the vlan switch option would have solved this problem but that doesn't appear to have existed before or after the 100D/200D unfortunately.