uninitialized constant Encoding (after loading $earthquake)

[ddd1600]

bash-3.2$ earthquake
_ _ _
___ __ _ _ | |_| | __ _ _ _ __ | | _____
/ _ / | '__| **| '_ \ / _| | | |/ ` | |/ / _
| __/ (| | | | || | | | (| | || | (| | < /
_**|,|| || ||, |,_|,||___|
|| v0.9.2

/Library/Ruby/Gems/1.8/gems/earthquake-0.9.2/lib/earthquake.rb:17: uninitialized constant Encoding (NameError)
from /Library/Ruby/Site/1.8/rubygems/custom_require.rb:55:in gem_original_require' from /Library/Ruby/Site/1.8/rubygems/custom_require.rb:55:inrequire'
from /Library/Ruby/Gems/1.8/gems/earthquake-0.9.2/bin/earthquake:42
from /usr/bin/earthquake:23:in `load'
from /usr/bin/earthquake:23
bash-3.2$

[no6v]

At the beginning of the README.md:

Terminal-based Twitter Client with Streaming API support. Only supports Ruby 1.9.

Check your ruby version. I'm using earthquake.gem w/ 2.0.0dev, though :).