DECT SIP system that supports off-hook dialing?

I am trying to find a DECT SIP phone system to replace an old analog DECT phone, which is connected to a PAP2T ATA.

These are my home phones, so I’ve done everything possible to make them act like traditional analog phones. In particular, I use “off-hook” dialing. The ATA is configured to connect to Asterisk as soon as a phone goes off hook, and I use the DISA application to implement a decision tree. This allows my dialplan to immediately recognize international numbers of various lengths, without waiting for a timeout or # key.

The PAP2T dialplan is (S0<:>). I also have a Polycom SoundPoint IP 321 in my home office, and I have configured its “home” line to behave in a similar fashion by setting call.autoOffHook.2.enabled="1" in its configuration file.

Does anyone know of a DECT system that offers this type of functionality?