My Konftel is connected to a PBX. I follow the instructions for multiparty calls, but it doesn't work.
1. Your PBX does not support mulipart calls. Contact your PBX reseller for upgrading.
2. Your PBX needs another command than R3 to connect more parties, read the table below. Note that the commands can differ due to settings in the PBX.
Brand Model Instead of R3 Instructions
Avaya IP Office *47 (default)
Ericsson MD110 3  
Euro Generis R63  
Philips Sopho IS3000 R R*3 for new line
Samsung Office Serv 500 46  
Siemens Enterprise Communications HiPath *3  or R*3 or *53
Siemens HiCom Office *5  
Vox Novo R4