[Asterisk-Users] Transferring calls from a Zyxel P2000w

[Esteban Barrientos Abarca]

Hello every body!
I'm having problems with a Zyxel P2000W phone, it looks i'm unable to transfer call from this phone.
The entry for the phone in sip.conf is this one:

[andy1]
type=friend
username=andy1
host=dynamic
dtmfmode=rfc2833 ; Choices are inband, rfc2833, or info
context=sip

In extensions.conf i have this:

exten => 206,1,Dial(SIP/andy1,40,trT)
exten => 206,2,Voicemail(u${EXTEN})
exten => 206,3,Hangup
exten => 206,4,Voicemail(b${EXTEN})
exten => 206,5,Hangup

On the phone i have the firmware version WJ.00.0a
With the G729 codec.(Yes, i tried G711.u and G711.a)

Asterisk version: Asterisk CVS-HEAD-07/27/04
I have cisco 7960 in my system as well but with those i can transfer calls, so my question now is, is it a configuration issue in my asterisk or is it just that the phone limitation?

Thanks in advance,

Esteban