rails3 installtion help

Ruby and rails version already on my system were 1.8.6 and 2.3.5
And I followed railscast 200 .Everything I did as root. I am on fedora11

As an example if do rvm 1.9.1 --default and then

ruby -v I get exact correct result as
ruby 1.9.1p378 (2010-01-10 revision 26273) [i686-linux]

    But when type rails -v I get it as rails 2.3.5
  But gem list shows rails3 beta as installed. What the reason might
be? Thanks for your help