Hi,
The self labling keys of the OpenStage 40T phone will not work on the Siemens HiPath DX (iSDX).
From the HiPath DX Electronic Publication:
"Note: Although the OpenStage 40T can be used on the HiPath DX, the DTU card to which it connects cannot support SLK operation. It is therefore only available for special orders where an OpenStage phone with a headset capability is required.
From Ver. 10 the OpenStage 30T is available. This has a headset capability."
Cheers,
Stoney