Can't turn off CONFIG_NET_ESTIMATOR on 2.6.17.7

I Recently built a 2.6.17.7 and wanted to turn off CONFIG_NET_ESTIMATOR 
but can't using menuconfig.

Is it on by default now, or is it a config issue?

I wanted it off to play with chains of policers and unless I 
misunderstand it uses Hz, and is inaccurate when Hz=250 with its' 
minimum time of 1/4 sec - which is too high for what I wanted anyway.

Andy.