cannot start listen command

[Sverker Sikström]

Hi

This is probabaly a very simple questions, but I am stuck and new to 
Octave. I am trying to run the command 'listen' 
(http://octave.sourceforge.net/doc/f/listen.html) on Octave. But it does 
not seem to find the command:

octave-3.0.1:46> listen
error: `listen' undefined near line 46 column 1
octave-3.0.1:46>

Have I not installed Octave correctly? I am using mac 0s 10.5. 4. Any 
help is appreciated!

Sverker