got a problem here and I hope you guys can help me...
I hope it's in the correct topic

8 years ago we installed DECT onto our domain.
This year we have built a new location and because WIFI coverage was needed, we decided to take the most budget effective option (8 more AP and we were covered) to deploy WIFI-phones (ASCOM I62) and in between a WIFI Bridge.
But now a problem rises...
We have a emergency number...
Our boss want that people that carry that phone to be always reachable.
So my cheap solution (OK not so clean), was to combine a DECT, WIFI and a Mobile into one number...
Just let them ring all 3 at the same time, no hassle.
Ok I tried a few things:
1) I converted the number into a huntinggroup and tried forwarding the call from the DECT onto the mobile.
This didn't seem to work, I think because the number called was the hunintingroup number, if number is called directly it does work.
2) I converted the number into a huntinggroup and added a virtual number which was immediately forwarded.
But also no joy
3) I made the number a virtual number and supervised the set with a virtual number.
This doesn't work because there is no multiline on the virtual set...
Is there a way to do this without buying SIP Mobilephone?
Any simpel ideas?