Also ring feature doesn't work for calls to queue number

Also ring feature doesn't work for a queue when set up in desktop client. When phone number is added as "also ring" or "forward to", calls to queue do not ring that number, calls go to voice mail if other attendants not avail. Added phone rings only if calling assigned user number. Call forwarding and simultaneous ringing to external phone numbers is enabled in the calling policy. Am I missing some settings?