EllisLab/CodeIgniter — pull request #1531 by dixy (2012-06-25 21:13:21+00:00)
Title: Allow safe_mode to be manually set in the Email Library

For example, on Infomaniak ini_get('safe_mode') returns false so the mail() function uses its fifth parameter (additional_parameters).
However Infomaniak does not allow this parameter. I have to set safe_mode to on manually to get mail function working.