[Asterisk-Users] playing "i" invalid context to an internal user

[Joseph]

When the call comes from outside on a certain context to play "i"
invalid extension to an external user is easy just by enclosing in an
incoming context:
exten => i,1,Answer
exten => i,2,Playback(pbx-invalid)

How to play an this context to an internal user, internal user has
access to all contexts.

In sip.conf I have
[phone number]
type=friend
context=internal
...

in extension.conf 
[internal]
include => outgoing ; include the outgoing context
include => prompts ; allow internal extens to record prompts
include => tollfree
include => iaxtel
include => invalid

[invalid]
exten => i,1,Answer
exten => i,2,Playback(pbx-invalid)
exten => i,3,Hangup()

But this doesn't work when I press any non-existent extension I get
congestion. 

-- 
#Joseph