I've installed php 4.0.5 and function "array_unique" does not work correctly anymore.
The following code works with 4.0.3pl1 as it's supposed to do:
<?
$arr[0][] = 1;
$arr[0][] = 2;
$arr[0][] = 3;

$arr[1][] = 1;
$arr[1][] = 2;
$arr[1][] = 3;

$arr[2][] = 1;
$arr[2][] = 2;
$arr[2][] = 5;

$arr = array_unique($arr);

while(list(,$n) = each($arr)) echo implode(',',$n)."<br>";

?>
Output is :
1,2,3
1,2,5

But with php 4.0.5 it refuses to work and returns : 1,2,3

I've looked through source code "ext/standard/array.c" and revealed some differences between 4.0.3 - 4.0.5:

> set_compare_func(SORT_STRING); - 4.0.5
> set_compare_func(SORT_REGULAR); - 4.0.3

Some others functions array_*  also use SORT_STRING comparing instead of SORT_REGULAR

Best regards,
Konstantin,
http://itc-ua.com