Send host name in MC|PingHost FE01 ping?

[deathcap]

The FE01 ping MC|PingHost has a field to set the host and and port of the server you're trying to ping:

socket.write(new Buffer('fe01'+
    'fa'+ // plugin message
    '000b'+'004D0043007C00500069006E00670048006F00730074'+ // MC|PingHost,
    '0007'+ // 7+len(hostname)
    '4a'+   // protocol version (74, last)
    '0000'+''+ // hostname TODO
    '00000000' // port TODO
    ,'hex'));

I set them to an empty string and zero, and it seems to work. Presumably intended for multiple servers on the same host, can each respond to pings individually. Maybe should send it, although would complicate encoding (protodef?)