Persian keyboard in iOS, how to access?

A few weeks ago I came across a thread that stated that iOS had a persian keyboard built into it, but it was not readily accessible. There was some information on how to access the keyboard via some manipulation, but I didn't bookmark the page (...i know...fail) Can anyone help me out? I do not want to use an app, I know it is built in, just don't know how to access it...

Thanks!