"no proxy for" in browsers kubuntu 12.04

[Stefan]

Am Mittwoch, 14. November 2012, 18:11:54 schrieb Nils Kassube:

....
> seamonkey. Firefox has its own proxy settings in the preferences /
> advanced / network tab where you can configure how firefox connects to
> the internet.

yes, thats the way I configure the proxy settings, in network tab...
and that is, what is not working.
Proxy itself is funcional but not " no proxy for",
ex. no proxy for 192.168.0.0/24
on MSwin its running....

tia
Stefan