Hello. Just went through an annoying debugging session when I upgraded my machine from 10.6 to 10.8 and thought I could save someone else some time.
Two major changes happened which screwed me up.
In 10.6, if you started a Juce application from XCode, you would get an empty command line. In 10.8, you get a command line like this:
and unfortunately this subtly broke things.
The other thing, even more annoying, is that "localhost" seems to not work any more. I used to open sockets with the "localhost" symbol, and that worked fine - but now you need to explicitly specify "127.0.0.1".
I really don't know if this happened in 10.7, 10.8, or is some interaction with JUCE, but I thought I'd post this so someone with either issue might find it in a search.