Before we can use PPP in the container, we must enable the PPP kernel modules on the host system:
modprobe tun modprobe ppp-compress-18 modprobe ppp_mppe modprobe ppp_deflate modprobe ppp_async modprobe pppoatm modprobe ppp_generic
vzctl set [VEnumber] --features ppp:on --save
vzctl set [VEnumber] --devnodes net/tun:rw --capability net_admin:on --save
