T38 And fax issue

I am testing if i can fax from a T38 capable softphone named Kapanga
to brother intellifax1270e which is connected with handytone 502 which is also T38 capable . So i am trying ip to ip faxing in same netwrok or LAN.
I am using asterisk
I corrected chan_sip.c file from T38_VERSION_0 to T38_VERSION_1
as been told in voip-info.org and make install again.

I can make call from one sip to another but cannot Fax.

will this fax start just by dialing and it autmatically detect fax dialled?
I did not still installed Tiff and spandsp or faxtarisk do i have to do that
before proceeding for this to be accomplished?

Give me some idea and step . did any body try ?