T.38 Fax Using Gafachi

Does anyone have a working configuration that uses Asterisk 1.4 to fax over IP using Gafachi and T.38?

I haven’t been able to make a successful fax transmission over Gafachi. I am using a Grandstream ATA that supports T.38 and have already turned off ECC and slowed down the fax transmission on my fax machine.