Here is what I've tried.
I've edited /etc/ssh/sshd_config on the remote AIX system
X11Forwarding yes X11DisplayOffset 10 X11UseLocalhost yes
as well as set $DISPLAY
DISPLAY=localhost:10.0 export DISPLAY
connect via RHEL
ssh -X me@hostname
get the following output:
X11 connection rejected because of wrong authentication. X connection to localhost:10.0 broken (explicit kill or server shutdown)
xauth list doesn't print anything.