forwarding to gtalk

[diprufa]

I can´t understand this:

If I call from Xlite (voxalot account) to mi usrgmail@gtalk2voip.com everything works great.
When I set callforwarding default to usrgmail@gtalk2voip.com nothing works. I've tried shutting down xlite and phonne a sipbroker allias (voxalot account) from pstn.

If I dial *7621xxxx (sipbroker map code) from pstn, gtalk work perfectly.
I 've alsa tried forwarding to *7621xxxx@sipbroker.com and doesn´t work. (it works from xlite)

What could be the problem? Thanks in advance.