Description:
------------
This bug was introduced to me by a stackoverflow post 
http://stackoverflow.com/questions/13815287/union-two-associative-array-
php/13815578#13815578 I tested the behaviour with php 5.5 Alpha 2 and the "bug" is 
still there.

As of the documentation, it is said that array_diff uses an "internal function" to 
compare two elements.

As equality is the only thing that matters for array_diff I thought this internal 
function was something that "==" behind.

But even if two arrays are equal (same members) array_diff does not take it in 
account.

I mark it as a bug but it can only be a documentation problem.

Test script:
---------------
<?php 
$A = Array(
    array(
            'lable' =>"label0",
            'id_poste'=>1,
            'id_part'=>11
    ),
    array(
            'lable' =>"label1",
            'id_poste'=>2,
            'id_part'=>12
            ),
    array(
            'lable' =>"label2",
            'id_poste'=>3,
            'id_part'=>13
    ),
    array(
            'lable' =>"label3",
            'id_poste'=>4,
            'id_part'=>14
            )
);

$B = Array(
    array(
            'lable' =>"label0",
            'id_poste'=>1,
            'id_part'=>11
    ),
    array(
            'lable' =>"label1_X",
            'id_poste'=>2,
            'id_part'=>12
            ),
    array(
            'lable' =>"label2",
            'id_poste'=>3,
            'id_part'=>13
    ),
    array(
            'lable' =>"label3_X",
            'id_poste'=>4,
            'id_part'=>14
            )
);

var_dump(array_diff_assoc($B,$A));

Expected result:
----------------
Array(2){
    [0]=>array(3){
            ["lable"] =>"label1_X",
            ["id_poste"]=>2,
            ["id_part"]=>12
            },
    [1]=>array(3){
            ["lable"] =>"label3_X",
            ["id_poste"]=>4,
            ["id_part"]=>14
            }
}


Actual result:
--------------
array(0){
}