[root@centos ~]# vzctl set 102 --features ppp:on --save
Warning: Unknown feature: ppp:on
Bad parameter for --features: ppp:on

[root@centos ~]# rpm -q vzctl vzctl-lib
vzctl-3.0.23-1
vzctl-lib-3.0.23-1

[root@centos ~]# grep DEV /etc/vz/conf/102.conf 
DEVICES="c:10:200:rw c:108:0:rw "

root@centos ~]# lsmod | grep ppp
ppp_mppe               10372  0 
ppp_deflate             9728  0 
zlib_deflate           21912  1 ppp_deflate
ppp_async              15232  0 
ppp_generic            31884  3 ppp_mppe,ppp_deflate,ppp_async
slhc                   10240  1 ppp_generic
crc_ccitt               6144  1 ppp_async


[root@centos ~]# vzctl enter 102
entered into CT 102
[root@vz102 /]# ll /dev/ppp
crw------- 1 root root 108, 0 Dec 13 13:01 /dev/ppp
[root@vz102 /]# ifconfig ppp0 up
ppp0: unknown interface: No such device


[root@vz102 /]# /usr/sbin/pppd
/usr/sbin/pppd: This system lacks kernel support for PPP.  This could be because
.
.