On Sun, May 3, 2009 at 11:01 PM, seven <dujinfang@gmail.com> wrote:

Actually, for the "call back" agents, because the fifo use originate to start a new session, the new session won't hang up unless one agent answered or timeout. Agents will hear nothing and wait(member_wait=wait) on the queue or hanup(nowait) if caller hang up before an agent answer the phone. '

When you are using on-hook agents, it's presumed to be under low call volume, you can just set the agents to get popped
into the queue in nowait mode so if the caller changed his mind the agent will get a hangup.  Remember, if there are X customers in the queue, mod_fifo generates X outbound calls to try to service them.