It'll be just as easy to configure it via the web interface as the CLI.
There's not a lot you'll need to make it work directly connected on a piblic IP address on the internet via H.323
On the H323 Page, set the CallSetup Mode to Direct, give the device a H323Alias ID (ie a name), make sure that H323 mode is turned on on the NetworkServices and you should be good to go to dial an IP address.
If your router is doing the NAT, you'll also need to congfiure the NAT settings on the H323 page.
There's another thread here - https://supportforums.cisco.com/message/4130618 - that has some more information - it's about an SX20, but the C40 is basically the same configuration wise.
Wayne
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Wayne
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