core_user_create_users custom field not add

Hi 

Hi everyone,
I am trying to create a user using api core_user_create_users with custom fields with the following array. the user is created but the custom field is not loaded, does anyone know why he does not load it? Thanks for your time!

Array
(
    [username] => nnnnn@gmail.com
    [password] => A123789456A
    [firstname] => nnnnn
    [lastname] => nn
    [email] => lesenda.gaston@gmail.com
    [idnumber] => A123789456A
    [customfields] => Array
        (
            [0] => Array
                (
                    [type] => dir
                    [value] => 02
                )

        )

)