inn -2.2.1: nnrpd is very slow talking to clients

[Colin Yuile]

I have installed inn-2.2.1 on a FreeBSD 3.3 machine using the traditional
storage method, and all seemed fine for a couple of weeks until I managed to
disconnect the machine briefly from the network. Since then news has been
received properly, but news readers take a very long time to connect. The
machine has been rebooted, and the database files rebuilt. The names of the
client machines resolve correctly on the news server machine, and I have no
trouble telneting to port 119 on the server from a client. 
 
When I attempt a connection from a news reader (such as knews). The news reader
 says that it is connected to the server and reading the active file, but it
hangs at this point for quite a long time. On the server the nnrpd process has
been forked:

nnrpd: my.client.machine.gov.au LIST (nnrpd)

and according to ps it is sleeping and has reduced its priority.
Eventually knews will move onto retrieving group descriptions, and after
several minutes I will be able to read news.

Any troubleshooting suggestions would be greatly appreciated. 

Colin