Simple Script for URI Handling
This technique works for me.

Here are some other relevant answers from around Stack Exchange:


Where does Mac OS X store file association information?
How do I configure custom URL handlers on OS X?
How can I manually change default applications in OS X?
How does Mountain Lion set the default text editor for the “open -t” terminal command?
Is it possible to query the launch services database for applications that will open an arbitrary file or UTI type?
How to remove an URL protocol default handler


A couple of relevant utilities are RCDefaultApp and duti.