1) su (sudo -s)
2) nano /etc/network/interfaces
3) search:
# iface eth0 inet DHCP
4) change on:
iface eth0 inet DHCP
hwaddress ether **:**:**:**:**:** (write your MAC)
5) reboot PC
---
PS: work on gnome 3 or next. On 2 or down is FAIL!!
---
metodic 2 (to reboot PC. When next start write again!!!):
su
ifconfig eth0 hw ether **.**.**.**.**.**
reboot eth0