Where do I put a file fixing timestamp functions in PHP 5.2?

[eluser]kingnutter[/eluser]
Hi there,

I am deploying a CI application to a live server. It is a VPS running PHP 5.2 (I don't think I can upgrade) which is incompatible with some of the later timestamp functions I have used on my development platform.

The functions are used in my navigation bar so need to be loaded on every page.

I have found a fix here and simply need to know how to incorporate the file in my application.

Do I need to create a helper file or is there a CI functions.php to which this can be appended?

Any help appreciated.

Many thanks,
Gary