Dialplan Function Volume (Rx|Tx) do not Works

Hi folks!

           I have installed an Asterisk 1.6.0.15 on a FreeBSD server and when I tried use dialplan funtion Volume() I did not realized any changes on volume/gain on SIP channels. This feature is new and is only available at Asteriak 1.6 versions and acts as AGC() function increasing or decreasing any type of channels audio volume. I saw /funcs directory and func_volume.c was there and func_volume.so is present on system. I unload and load this module by CLI interface but it do not works yet.

Any idea?

Sds,

Sérgio Brito