Don't know if you guys have the Kirk Dect solution that we have in Oz. It was also sold under the Polycom brand but was effectively a replacement for the PHS system. Here in Oz people were looking for an alternative to the industrially rated handsets that were normally associated with the system and it has been found that the Siemens Gigaset handsets can be used. However the problem is that the gigaset uses a different registration code to the Kirk (one uses IPUI and the other uses IPEI, if I have that right) However I have come across a site that has a downloadable spresdsheet that allows you to convert the Gigaset code to the Kirk/Polycom code. If it is of use, it can be found here.....

https://www.australiancommsforum.co...on-6953669?pid=1283262772#post1283262772