asterisk users - Dec 2006 - G.726 on Asterisk 1.4.0

I'm trying to make a new box with Asterisk 1.4.0, work with one ATA
GrandStream 496 and G.726.
 
However I modified the rtp.c as suggested for the Sipura's ATA with
USE_DEPRECATED_G726=1 is not working.
 
Someone knows about this?
 
Thanks,
 
Carlos Alperin