One of the boxes which my GSP owns appears to have a slight problem with
Call of Duty. When I try and start a CoD server, it gets to the point just
before it would normally assign itself its IP / port, but it hangs there
instead. Traces of what happens can be found at the following URL. There is
a trace of the bad server (it hangs where the trace stops), and a good
server (it continues to load up after where I've cut the trace).

http://www.cfadams.co.uk/trace.txt

Issues which aren't the problem:

- Configuration - it's all been generated by my central system and deployed
as it would on any other box. Manual minimal tests also prove useless

- Game files - the md5s match and permissions are fine

- External hardware-related network problems - this is very unlikely as
there is another box in the same subnet / connection working just fine,
although there could be something wrong with the box itself I suppose.

I'm missing the immediate clues if there are any, so I can't really
elaborate in a useful way, but if any of you have any specific questions, or
want me to check / try something, please ask.