#array overwriting
Array (
     [NM1] = array(
            [0] => GTHHS
            [1] => MEKID Interface
            [2] => 5496
            [3] => 2012-07-20
            )
);

Array (
     [NM1] = array(
            [0] => GTHHS
            [1] => MEKID Interface
            [2] => 5496
            [3] => 2012-07-20
            )
);

#output
Array (
     [NM1] = array(
            [0] => GTHHS
            [1] => MEKID Interface
            [2] => 5496
            [3] => 2012-07-20
            )
);


#desired output

$array1 = Array (
     [NM1] = array(
            [0] => GTHHS
            [1] => MEKID Interface
            [2] => 5496
            [3] => 2012-07-20
            )
);

$array2 = Array (
     [NM1] = array(
            [0] => GTHHS
            [1] => MEKID Interface
            [2] => 5496
            [3] => 2012-07-20
            )
);