Dynamic IP but DNS static (3g connection)

[Xavier Callejas <xavier wflogistics com>]

Hi,

I am impressed by the fact that knetworkmanager has an option for my ttyUSB0 
3g modem connection.

I spent about 8 hours trying to get connection with vodafone, kppp, etc.; I 
found the option in knetworkmanager by any chance :p  and it was very easy.

My connection is a 3g.

The IP configuration is provided dynamically but ...

I don't know why when I use this modem with linux the ISP provides another DNS 
servers than when I have used it in Windows; I always have to change 
the 'resolv.conf' manually because the dns servers provided do not work (but 
this problem occurs using kppp, vodafone, knetworkmanager, pddd). 

I want to configurate a fixed dns server for this 3g connection in particular.

How can I do this?

Thanks.

-- 
Xavier Callejas