Install JRuby 1.7.9
Dowlnoad Apache Mahout archive.apache.org/dist/mahout/0.9/mahout-distribution-0.9-src.zip and descomprese it at /bin/mahout
Create enviroment var at you bash.rc or barch.profile including export MAHOUT_DIR=/bin/mahoutp
Verified you have installed Virtual Java Machine (VJM)
Please visit jruby mahout to check documentation github.com/daifu/jruby_mahout