Set the default encoding to UTF-8.
Set the default encoding to UTF-8.

After making myself a little shell script to run on build of a scheme in Xcode, it would always fail on me, even though running it from the terminal worked fine. Setting the default encoding to UTF-8 seems to fix this issue.

Reference: https://github.com/berkshelf/berkshelf-api/issues/112 (near the bottom)
It's an encoding thing, notice how the JSON parser is trying to use US-ASCII as it's encoding. As of ruby 1.9 the encoding for JSON parser is explicit so you can either add this to the berks executable:
Encoding.default_external = "UTF-8"

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