I went trawling through some old mailing list threads and discovered that the solution is to use a channel bridge through loopback: <extension name="inbound_ivr"> <condition field="destination_number" expression="^inbound_ivr$"> <action application="answer"/> <action application="sleep" data="1000"/> <action application="ivr" data="evariste_ivr"/> </condition> </extension> <extension name="inbound_ivr_6789540670"> <condition field="destination_number" expression="^(6789540670)$"> <action application="bridge" data={presence_id=6789540670@pbx.corp.evaristesys.com}loopback/inbound_ivr"/> </condition> </extension> This will link the presence entity 6789540670@pbx.corp.evaristesys.com to the state of the bridge. A static BLF directory key can then be provisioned on the Polycom and voila! -- Alex Balashov - Principal Evariste Systems LLC 235 E Ponce de Leon Ave Suite 106 Decatur, GA 30030 United States Tel: +1-678-954-0670 Web: http://www.evaristesys.com/, http://www.alexbalashov.com/