X forwarding via ssh not working

Question

hi!
since i've updated to leopard, i have no longer been able to forward X sessions via ssh (ssh -Y $username@$remotehost)
i can login into the remote host, but X forwarding simply doesn't work, i.e. the app never opens. i've tried with vlc mainly.
also i've noticed that if i try starting an app like xclock locally, it doesn't show up.
here's the content of DISPLAY locally
Macintosh:~ asymmetric$ echo $DISPLAY
/tmp/launch-35MU2b/:0
while on the remote machine it's something along the lines of
localhost:12.0
i haven't updated to the "unofficial" xquartz releases, so the openssh version here is OpenSSH_4.7p1, OpenSSL 0.9.7l 28 Sep 2006
any ideas?
thanks
asy

Answer 1

i forgot to mention it, but i'm trying to connect to a GNU/Linux box. Don't know if it's the same for you.
I do have a Linux system at the other end of my ssh -Y connection (RHEL4).
From the RedHat system I see the following information:
% printenv | grep -i ssh
SSH_CLIENT=::ffff:xxx.xxx.xxx.xxx 60264 22
SSH_TTY=/dev/pts/13
SSH_ASKPASS=/usr/libexec/openssh/gnome-ssh-askpass
SSH_CONNECTION=::ffff:xxx.xxx.xxx.xxx 60264 ::ffff:yyy.yyy.yyy.yyy 2
% grep X11Forwarding /etc/ssh/sshd_config
X11Forwarding yes
% echo $DISPLAY
localhost:15.0
The following is the Mac OS X info:
% echo $DISPLAY
/tmp/launch-MoVGGO/:0
% grep X11Forwarding /etc/ssh/sshd_config
X11Forwarding yes
% ssh -Y remote.system.address
Make sure you are not setting your own $DISPLAY environment variable.
Do you have a $HOME/.xinitrc ?? If so, how much does it differ from
/usr/X11/lib/X11/xinit/xinitrc