Facebox open from ajax respond text not work properly

Facebox open from ajax respond text not work properly

I have a problem with jQuery plugin "facebox".
here is the script in php
echo"<a href='confirm.php' rel='facebox' id='$row[mynr]'
onclick=\"activatefacebox('$row[mynr]'); return false;\" ></a>";
In javascript
function activatefacebox(id_post) {
var sss="#"+id_post;
jQuery(document).ready(function($) {
$('#sss').facebox({
loading_image : '../img/ajax-loader.gif',
})
})
}
My problem is : The first click it´s not work, you have to click it again
and it will open the facebox, but with 2 boxes. And when you click the
link the box will increase from 2 to 3 to 4 etc.
I have no idea how to fix this. But it work fine with pure php without ajax.