When you select to enable network packet forwarding under the routing
section, it updates /etc/sysconfig/network but not /etc/sysctl.conf. From
what I understand /etc/sysctl.conf is what dictates the ip_forward option
now in Red Hat 6.2. Therefore, enable network packet forwarding with
netcfg does not enable packet forwarding at all
This is fixed in the versions of pythonlib and netcfg that we have in Raw Hide
(ftp://ftp.redhat.com/pub/rawhide/noarch/RedHat/RPMS/). We haven't yet decided
whether or not to issue them as a bug-fix erratas.