Is your phone rootet?
if that is so, then goto "/etc/wl/" or "/wifi" with a root explorer and edit the NVRAM.txt
You will find this in file"#il0macaddr=YOUR ADDRESS" - change it - save it - reboot your phone
if it works give me report :)
I do it with my Sony Xperia Z.
And I have changed the MAC ADDRESS with my program
http://gbatemp.net/threads/has-anyone-attempted-to-abuse-the-nintendo-zone-streetpass-relay.352410/page-19#post-4736261
for all those have problems to change the mac address of the android device, here is my Android MAC Address changer!
(THIS IS AN TEST VERSION! USE IT ON YOUR OWN RISK!)
http://www.cruxload.com/gbatemp/AMC-0.0.0.2.zip