I am unable to set following mac address "36:AA:42:FB:B9:57" with /etc/config/wireless file, But with mac address "36:AA:42:FB:B9:58" interface is up.
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        a  MAC address should have 0 as a least significant bit (unicast) and 1 as a second least significant bit (locally administered) in the second nibble.  Thus possible values for the second nibble are limited to 2, 6, A and E.
        In other words
        MAC address:  “XY-XX-XX-XX-XX-XX” “X” can be anything hexadecimal.  The hexadecimal “Y”, written in binary format, is  Y:  “kmnp”,  where “p” is the least significant bit;
                p=0 --> unicast;
                p=1 --> multicast;
                n=0 --> globally assigned MAC;
                n=1 --> locally administered;
        So, actually MAC can be changed  to any combination in which p=0 and n=1;
        “Y” can be 2, 6, A or E.
        So the possible MAC addresses in Windows 7 for wireless adapters:
        X2-XX-XX-XX-XX-XX
        X6-XX-XX-XX-XX-XX
        XA-XX-XX-XX-XX-XX
        XE-XX-XX-XX-XX-XX

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