Configuring FreeBSD Jails
From ZS64
After creating a jail in FreeBSD, the default configuration of many subsystems should be adapted to better suit the restrictions in a jail.
sshd
Normally, sshd will create X11 connections on the localhost host address only to improve security. Since jails don't have a loopback address, X11 forwarding only works if sshd uses a wildcard bind for the X11 connections.
In /etc/ssh/sshd_config, add:
X11UseLocalhost no
