I probably should have responded to this one first. Yes, you are heading down the right track, but you don't need to put that godaddy supplied code anywhere. It is already incorporated into zen-cart and the AP module. The code isn't exactly the same, because the zencart code makes use of a few more variables, which is why zencart can have 'global' settings for the cURL proxy/port, rather than being hard coded into each of the modules that require them.
Having said that, if you take a look at the cURL related code in the austpost.php script (where you commented out that debug line) you will find that the code is very similar to what you found on godaddy.
Bottom line.... nothing for you to do in this regard, especially if you can get a quote on the prepaid satchels by making the http/https change as per previous message.
Cheers
Rod
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