[rohitarondekar]

Actually ruby 1.8.7 is required to install ruby 1.9.2. Rails doesn't need 1.8.7 and works fine with just ruby 1.9.2 installed.

  ruby - Ruby itself is prerequisite in order to build Ruby 1.9. It can be 1.8.

source: http://redmine.ruby-lang.org/wiki/ruby/DeveloperHowto#label-...

[getsat]

If you install via RVM, you don't need a system ruby or anything else installed for bootstrapping.

http://rvm.beginrescueend.com/rvm/install/

http://rvm.beginrescueend.com/deployment/system-wide/