ssh unable to listen to port

[Dan Christensen <jdc@jhu.edu>]

I'm using 

ii  ssh            1.2.2-1.4      Secure rlogin/rsh/rcp replacement (OpenSSH)

on a recently updated woody system.  I often use ssh to forward ports.
Sometimes ssh refuses to do so:

root@scratchy:~# ssh -L 119:news.jhu.edu:119 jdc@chow 'sleep 60000'
Disconnecting: cannot listen port: 119

The previous copy of ssh is no longer running, so the port should
be free.  How can I find out what is preventing ssh from listening
to the port?

Thanks for any help,

Dan

PS:  Here is an excerpt of the output when ssh is given the -v flag:

debug: RSA authentication accepted by server.
debug: Connections to local port 119 forwarded to remote address news.jhu.edu:119
debug: Local forwarding listening on 127.0.0.1 port 119.
bind: Address already in use
Disconnecting: cannot listen port: 119

-- 
Dan Christensen
jdc@math.jhu.edu