Avaya IP phone and I-240W-A Router

[thegiantsmurf]

We have an Avaya IP phone, sat in Mexico on a telmex connection via a I-240w-A router.

It registers correctly with our Avaya telephone system, presence is shown correctly, and when
someone in the UK calls the phone, it rings, you can answer it, and the conversation proceeds as expected.

However, if the phone in Mexico calls a phone on the system in the UK, the phone rings correctly,
you get caller id to see which extension is calling, but when you pick up, although the system timer
counts up as though a call is in progress, neither of the callers can hear the other caller.

Essentially UK to Mexico works fine, Mexico to UK, silent calls.

One suggestion I have had is to telnet to the router and disable H323.alg and Sip.alg protocols on the router.

Can anyone tell me if this is likely to fix the problem? If so, can you also tell me the relevant commands?

Alternatively, has anyone any suggestions I can try to get it working?

Thanks
M,.

[cavagnaro]

Ummm we are Alcatel forum, not Avaya.
No clue on those products