Polycom Group Call Pickup

On Polycom phones (501, 500, 650, etc.) I can activate the “Group Call Pickup” feature:
In sip.cfg:
… feature.11.name=“group-call-pickup” feature.11.enabled=“1”

Then when I lift the handset, that soft-key is available. But, when I push it, FreePBX (Asterisk) does not seem to handle it correctly.

This issue was discussed a few years ago here
http://lists.digium.com/pipermail/asterisk-users/2005-June/104459.html

But I am wondering if anyone has solved it since then?
Or, is there any way to program the Polycom to send the *8 when that key is pressed (just like it sends *69 when Last-Call-Return softkey is pressed)?

Yes, *8 works on my system (since I have it in the phone’s Dialplan [SIP “Digitmap”]). But I want to use the more user-friendly softkey that is built into the Polycom phone.

Thank you