[Users] Re: Conference is Not Working.... with OpenSER And, Asterisk

[Paul Smith]

This is an Asterisk config problem rather than an OpenSer one.
The conference applications in Asterisk need a timing source.  If you
install a Digium or Sangoma card then Asterisk will use it as a timing
source.  As you are not using such a card you need to compile and
modprobe a module called ztdummy to create a pseudo timing device.