Problem with changing mac address in Ubuntu, solved...

I was trying to change the mac address in network, but when I add new mac address to a connection, it was creating another connection and use it.
Then I do this:

In Terminal:

sudo gedit /etc/network/interfaces

It will bring up a document, I just added few lines, so it looked like this:

auto lo
iface lo inet loopback
auto eth0
iface eth0 inet dhcp
hwaddress ether 02:01:02:03:04:01

then i've save and close.
then in the terminal, i've run this commands:

sudo /etc/init.d/networking restart
ifconfig

And that's it. It worked for me.

Thnaks,
Sakib