Modify LAN Settings

[Prakash Krishnaswamy <prakash krishnasamy mobax com>]

Hi,

In my application I need to modify the IP address settings for eth0, 
eth1, wlan, etc.
For this I had directly modified the file /etc/network/interfaces (in 
ubuntu).
I would like to do it in a proper way using the NetworkManager.
Can somebody tell me where to look out for the source, which library I 
have to use?

Thanks,
Prakash