IAX client directly answer for some users

Hello, I have a really strange behavior of my IAX clients (tried with Iaxcomm and Firefly with the same results)… I use asterisk 1.2.11.

2 users with exactly the same definition. I call the first (ruser) from a SIP client, the softphone ring normally, and I can answer.

When I call the second (tuser), the called softphone directly answer without ringing, and the calling phone is still ringing. The flow from the calling to the caller is already active at this time !

The problem even occurs when I call the same softphone registred with the 2 accounts at the same time, and after a restart of *…

in IAX.CONF :

[code][tuser]
type=friend
context=FromInternal
auth=md5
secret=passT
host=dynamic
notransfer=yes

[ruser]
type=friend
context=FromInternal
auth=md5
secret=passR
host=dynamic
notransfer=yes[/code]

in EXTENSIONS.CONF :

exten => #500,1,dial(IAX2/ruser,,Tt) exten => #501,1,dial(IAX2/tuser,,Tt)

In the logs *, and in a network trace, I don’t see any difference between the 2 calls, except that the voice flow start directly in one direction for tuser…

Any idea ?

Thanks

Robert