global configs for pagination?

[eluser]w1n78[/eluser]
i'm trying to set $config values for the pagination class so that it can be used throughout the application without having to set it in every controller class. i created a My_pagination class that extends CI_Pagination and i get an error...

Code:

/* Location: APPLICATION_PATH/libraries/My_pagination.php
*
*/
class My_pagination extends CI_Pagination
{
public function __construct()
{
  parent::__construct();
  
  $this->full_tag_open('<p class="pagination">');
  $this->full_tag_close('</p>');
}
}

Fatal error: Call to undefined method My_pagination::full_tag_open() in... line 9

what am i doing wrong? is this the right approach? i just want to set the open and close tags for the page links and set the per_page. this was the same approach i used for extending the CI_Form_validation class and it worked, why doesn't this one work?