Nope, but your AT commands are part of the equation.

To get a feeling for what you are up against without necessarily having to fork out money for all the relevant standards, find a copy of "C Programmers's Guide to Serial Communications" (preferably 2nd edition) by Joe Campbell at your local bookstore or library. In this book, facsimile has its own 70+ page chapter in enough detail to discourage the faint of heart. It also includes an example session for transmission of a single page with an EIA/TIA 578 Class-1 modem and the AT commands to do so (the AT commands being the smallest part of the problem). Do let us know how you get along with your project.