You can change default email sending policy. Default is return type of phpmailer object interperteted as true means send.

This can be used if you wanted to use your own mailer rather then default phpmailer. This hook may be used with additional hook.

https://www.opensource-socialnetwork.org/documentation/view/5559/mail-send

<?php
function my_component_init(){
		ossn_add_hook('email', 'send:policy', 'my_component_hook');
}
function my_component_hook($hook, $type, $allowed_or_not, $instance){
		return false;
}
ossn_register_callback('ossn', 'init', 'my_component_init');