DISCLAIMER: This is solely for those who have lost and intend to restore their WLAN MAC address after a bad flashing of their ROM, otherwise it will be deemed illegal.
It is recommended you make a NVRAM backup..
1. Switch off your WLAN connection.
2. Launch the Dialer and key-in *#*#3646633#*#* and you will enter the Engineering Mode, as shown below:-
3. Swipe to Connectivity Tab from the image below:-
4. Click WLAN > NVRAM;
5. Enter the “Byte String Access:” values, as shown below:-
6. Click Read, a 12 digits value will appear in “value(h):” field which is your current WLAN mac address. Please jot it down for future reference. As shown below:-
7. Delete the value(h) field and now enter a new 12 digit mac address, and click Write.
8. Press your home button and switch On your WLAN connection.
9. Goto About phone > Status > WLAN MAC address, check accordingly.
"Solving with simplicity"