What is the syntax for the "Do not use proxy for:" field of the "Proxies" tab in the "Advanced settings" of a connection setup?

I have the settings working properly for browsing to external web servers through a proxy but I also need to directly access web servers on my local network.

Lets say I have a local server that I access as
http://myserver.mylocal.net/

If I set the "Do not use proxy for:" field to
mylocal.net
my N800 with OS2008 still tries to use the proxy to access the local server above (as indicated by the proxy server's logs).

Also, I sometimes need to access local web servers using their IP address, because it's not in the DNS server's database, (these are temporary servers, so we don't name them via DNS). E.g.:
http://172.16.1.5/

What's the "Do not use proxy for:" syntax for a numbered IP network? I've tried
172.16
172.16.0.0
172.16/16
172.16.0.0/16
172.16.0.0/255.255.0.0
even 172.16.1.5 for a single server
None of the above work.

Last question; What separator should be used for multiple network entries in this field?