I've been using a work around with SSH that helps. Once you get knocked back into that login screen and you can't connect, paste this script into an SSH client (Secure Shell client on Windows or terminal on a mac)
osascript <<EndOfMyScript
tell application "System Events"
keystroke "Chu"
delay 5.0
keystroke return
delay 5.0
keystroke "password"
keystroke return
delay 1.0
keystroke return
end tell
EndOfMyScript
My first keystroke says "Chu" because my login name on that mac is Chuck, so replace it with the first 3 letters of your user name (assuming you use the welcome screen type login).
Obviously you have to have SSH preconfigured on the remote mac and you have to establish the connection first. Run the script as root!!