This short tutorial is how to get Ruby 1.9.1 on BT4 or any other Linux distro with the tool 'rvm' (Ruby Version Manager).
The Metasploit team has put a lot of work into getting the framework to work well with 1.9.1 and still work with earlier versions. Here is a way that you can try out the new hotness, or just test to see if all of the tweaks and modules you run work with the newer version of ruby.
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