OK, that's good to know. How about loading it into the iPhone kindle app? Is downloading into the Kindle app through Safari from the Calibre content Server supposed to work?
I honestly don't know. I'd guess it would depend on where Safari is downloading the file _to_. The aforementioned thread implies that the file needs to be in a very particular location in the iPhone's (or the Kindle 4 iPhone program's) directory structure for the process to work. That's why most were using a third-party app to transfer the files to the iPhone manually.
I don't have a smart-type, app-phone to test these things on, myself, unfortunately (actually, I consider myself quite fortunate in that regard, but you get the gist