There should be no problem "type" or any other field name. o.O Probably you classes were out of date, as I said.
Impossible, no, they were not.
I've changed the code several times, everytime I changed something to test, whether the change makes it work, I restarted both server and client (which were both compiled with the newest code, of course).
Between two times running I simply changed the name of the variable from "type" to "connectiontype" and it worked.
It's impossible I could have had two different class versions between my server and client.