UCP Register: Non-static method phpbb_captcha_factory::get_instance() should not be called statically

I get the following error when viewing ucp_register module:

Strict Standards: Non-static method phpbb_captcha_factory::get_instance() should not be called statically, assuming $this from incompatible context in (...)\includes\ucp\ucp_register.php on line 164

Strict Standards: call_user_func() expects parameter 1 to be a valid callback, non-static method phpbb_captcha_gd::get_instance() should not be called statically in (...)\includes\captcha\captcha_factory.php on line 38

Both functions referenced should be made static.