Brother Printer using internal I-Fax subsystem and Tiff-f file format

I was just wondering if anyone out there has gotten this to work?  At several clients I have Brother MFC/AIO Printers.  The printers have a function called I-Fax(Internet Fax). The primary function recieves faxes in and forwards them to an email in PDF or tiff format.  This works great; but the other side is that it will recieve an email in and fax it out.  This function is more limiting and requires a tiff-f format. Yes that is all the information that Brother gives.  I am successful if I forward an image recieved from the fax machine back out.  But, I can not get a single PC/software generated tiff-f to be recognized by the MFC.  Any insite would be greatly appreciated.