[tor-dev] Link protocol version

I'm trying to understand link protocol versions, but I have some problems. I requested descriptor from the root server and it contains line "protocols Link 1 2 Circuit 1". Then I connected to the node, sent VERSIONS cell and got a responce: "00 00 07 00 04 00 03 00 04". But according to that responce, the node supports link protocol v3 and v4, not v1 and v2. Could you please explain that moment?