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 "

[root@hn ~]# lsmod | grep ipt
ipt_MASQUERADE          1632  0
iptable_nat             7716  3
ip_nat                 13300  2 ipt_MASQUERADE,iptable_nat
ip_conntrack           47300  4 xt_state,iptable_nat,ip_nat
ipt_ttl                 1568  5
ipt_TCPMSS              3552  5
iptable_mangle          3520  5
iptable_filter          3232  7
ipt_multiport           2496  10
ipt_tos                 1344  5
ipt_REJECT              4256  7
ip_tables              11356  3 iptable_nat,iptable_mangle,iptable_filter
x_tables               12544  13 ipt_MASQUERADE,xt_state,iptable_nat,xt_tcpudp,xt_length,ipt_ttl,xt_tcpmss,ipt_TCPMSS,ipt_multiport,xt_limit,ipt_tos,ipt_REJECT,ip_tables
[root@hn ~]#

[root@vps ~]# iptables -t nat -A POSTROUTING -s 5.5.0.0/24 -j MASQUERADE
iptables: No chain/target/match by that name
[root@vps ~]# iptables -L -t nat
Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

Chain POSTROUTING (policy ACCEPT)
target     prot opt source               destination

Chain PREROUTING (policy ACCEPT)
target     prot opt source               destination
[root@vps ~]#

[root@hn ~]# iptables -t nat -A POSTROUTING -s 5.5.0.0/24 -j MASQUERADE
[root@hn ~]# iptables -t nat -L
Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

Chain POSTROUTING (policy ACCEPT)
target     prot opt source               destination
MASQUERADE  all  --  5.5.0.0/24           anywhere

Chain PREROUTING (policy ACCEPT)
target     prot opt source               destination
[root@hn ~]#

[root@hn ~]# uname -r
2.6.16-026test018.1.custom
[root@hn ~]#