[Asterisk-Users] using iLBC

[nicolas]

I want use iLBC and have following in mind, please help me is it possible ?

ISDN <-----(ALAW)-----> * <-----(ALAW)-----> SNOM
SIP  <-----(iLBC)-----> * <-----(ALAW)-----> SNOM

1. ISDN incoming codec is ALAW SNOM codec should be ALAW (can't be iLBC
because a lack of codec).
2. SIP incoming codec should be iLBC (snom is ALAW).
3. SIP outgoing codec should be iLBC /snom is ALAW).

I thought * is converting beetwen iLBC and ALAW but * force the use of ALAW
always, because i can not disable ALAW (need is for ISDN).

So it is no solution like this is it right ?
Or can anybody help me want must i type in the sip.conf.

There was a discusion before, but have not understand is fully (sorry).

nicolas