# vzctl start 101
Warning: Unknown iptable module: ipt_MASQUERADE, skipped
Starting container ...
(....)

(...)
IPTABLES="iptable_filter iptable_mangle ipt_limit ipt_multiport ipt_tos ipt_TOS ipt_REJECT ipt_TCPMSS ipt_tcpmss ipt_ttl ipt_LOG ipt_length ip_conntrack ip_conntrack_ftp ip_conntrack_irc ipt_conntrack ipt_state ipt_helper iptable_nat ip_nat_ftp ip_nat_irc ipt_REDIRECT ipt_MASQUERADE"
(...)

# lsmod | grep ipt_MASQUERADE
ipt_MASQUERADE         35456  0 
ip_nat                 53520  6 vzrst,ipt_MASQUERADE,ipt_REDIRECT,ip_nat_irc,ip_nat_ftp,iptable_nat
x_tables               52744  18 xt_tcpudp,ipt_MASQUERADE,ipt_REDIRECT,iptable_nat,xt_helper,xt_state,xt_conntrack,xt_length,ipt_LOG,ipt_ttl,xt_tcpmss,ipt_TCPMSS,ipt_REJECT,ipt_TOS,ipt_tos,xt_multiport,xt_limit,ip_tables