vs_port: interface_type does not work

I'm trying to create an internal interface in vswitch ( latest version from github: df78b576 ) via:

vs_bridge { 'br-default':
    ensure => present,
  } ->
vs_port { 'int-iface':
    ensure => present,
    interface_type => 'internal',
    bridge => 'br-default',
}

however 'ovs-vsctl show' return:
...
     Port int-iface
            Interface br-default
                error: "could not open network device int-iface (No such device)"
...

Looks like interface_type value is broken for vs_port.