Attended call transfer is not updating called id on destinationHi,

[lblokland]

Hi,

We are using a fork of the T28p (not sure if that's the right word) - a Tiptel IP 286.
Now we are having issues with attended transfer..when ext 201 is calling 202, and in that call extension 202 transfers (attended) the call to 203, we want to see the CID 201 on phone 203. However it's still on 202.
I have set the setting in the phone to PAI and also PAI-FROM. Asterisk is set to sendrpid=pai.
I'm pretty sure everything is set ok in Asterisk, because when I replace the phone on ext 203 for another brand, this works just fine.
The Tiptel phone is on the most recent firmware, but that isn't upgraded in a long time. My guess it's the same as some V70 version.
However ,the supplier told me to load and test the original Yealink firmware.
When trying to load any Yealink firmware from the webinterface, all seems fine. upload is running, phone restarts, but the firmware stays with the Tiptel version.

Do you know if this Yealink firmware can be loaded and/or doe you know anything about setting the correct options to get the CID updated on attended transfer?

Cheers,
Leon