I started the server and got :
That was annoying.
I connected to the database from the command line and from another tool.
I ran rails console and got the following :
ArgumentError: syntax error on line 42, col 0: `' load at org/yecht/ruby/YParser.java:152 load at /home/[USER NAME]/.rvm/rubies/jruby-1.6.5/lib/ruby/1.8/yaml.rb:134 database_configuration at /home/
Taking a look at yaml.rb line 134 clued me in that I was using the wrong jRuby compatibility.
RVM to the rescue. RVM is just pure goodness. It really makes switching rubies a breeze.
The executive summary is that RVM makes it easy to run multiple versions of Ruby and/or Ruby gems. To use jRuby :
rvm use jRuby
It even makes it easy to set jRuby's version compatibility. RVM allows you to specify hooks to run after its' methods.
jRuby 1.6.x has 1.8 and 1.9 Ruby compatibility. To use 1.9 just add an "after_use" hook (this is detailed on the RVM site).