Hi all, I am trying to use XDMCP from a Mac (OSX Lion, XQuartz) to an updated CentOS 6 64Bit host. I am tunneling through SSH, so I use XDMCP on the remote host locally via Xnest like this: > ssh -X -C -l $LOGINUSER $HOST -n "Xnest :1 -ac -geometry 1440x850 > -once -query localhost I get a black screen without any login window or desktop background. My /etc/gdm/custom.conf looks like this: > # GDM configuration storage > [daemon] > [security] > DisallowTCP=false > AllowRemoteRoot=true > [xdmcp] > Enable=true > [greeter] > IncludeAll=true > [chooser] > [debug] According to the howtos on the net this should be sufficient, so I am quite stuck. How can I figure out if this is a problem of the CentOS config or of XQuartz? Any hint or help would be appreciated. Dirk