http://babilonline.blogspot.com.au/2012/06/ubuntu-1204how-to-use-vnc-even-at-login.html
found this - worked to get to the login screen to do the above workaround...
need to use a proper vnc client on osx though - not screen sharing:)
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You received this bug notification because you are a
I am experiencing this same issue, though I cannot use the workaround
above as I am running my ubuntu 12.04 machine headless as a media
server.
Using VNC to connect post logon does not allow me to choose a session at
logon, hence setting the defaults via command line is the only option I
have.
