Thank you very much, for your answer.
I've immediately post on joomprod adsmanager forum.
Now, I've tested this.
I've replaced in /components/com_adsmanager/views/details/view.html.php on line 102:
$results = $dispatcher->trigger('onContentPrepare', array ($content));
BY
$results = $dispatcher->trigger('onContentPrepare', array ($context, &$row, &$params, $page = 0));
Now it works, but I'm not sure that all work with this code.
I'll post joomprod forum answer as soon as I have.
PS : sorry for my english, I'm French.