Networking UNIX

Configure Solaris 10 to listen for X forwarding

I think you will also need to enable the x11-server listener as well.
$ svccfg -s x11-server listprop options/tcp_listen
options/tcp_listen boolean false
$ pfexec svccfg -s x11-server setprop options/tcp_listen = true
$ svccfg -s x11-server listprop options/tcp_listen
options/tcp_listen boolean true