[CentOS] Correct way to disble TCP Segmentation Offload (tso off) in CentOS 5

Hi,

What's the correct way to disble TSO (TCP Segmentation Offload) in RHEL5?

I have tried adding those options in ifcfg-ethX configuration file:

# grep ETHTOOL /etc/sysconfig/network-scripts/ifcfg-eth0
ETHTOOL_OPTS="tso off"

And also with:

ETHTOOL_OPTS="-K eth0 tso off"

But when restating the server TSO is enabled:

# ethtool -k eth0
tcp segmentation offload: on

As a temporary solution, I'm executing this command in a start script:

/sbin/ethtool -K eth0 tso off

But I think it can be configured in network configuration files, any 
idea to solve this? thanks!!

Regards,

-- 
Santi Saez
http://woop.es