Missing argument/parameter in hook

Hello

I’m developing an easy plugin and I need to run my task when a comment is approved.

I’ve added my action to the hook wp_set_comment_status like this :

add_action('wp_set_comment_status', 'myfoo' );

My function looks like :

function myfoo($comment_id, $comment_action)

the point is that I always get this message

Warning: Missing argument 2 for myfoo

when the action is called.

How is it ? Shouldn’t wp_set_comment_status be called with 2 params ?

Let me know.

—
Simone