当我>rvm安装1.9.2时，一切都很顺利。然后我做>rvm使用1.9.2，这也很好。
当它涉及到ruby -v虽然..

sam@sjones:~$ rvm install 1.9.2
/home/sam/.rvm/rubies/ruby-1.9.2-p136, this may take a while depending on your cpu(s)...

ruby-1.9.2-p136 - #fetching
ruby-1.9.2-p136 - #downloading ruby-1.9.2-p136, this may take a while depending on your connection...
% Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                               Dload  Upload   Total   Spent    Left  Speed
100 8612k  100 8612k    0     0   562k      0  0:00:15  0:00:15 --:--:-- 1305k
ruby-1.9.2-p136 - #extracting ruby-1.9.2-p136 to /home/sam/.rvm/src/ruby-1.9.2-p136
ruby-1.9.2-p136 - #extracted to /home/sam/.rvm/src/ruby-1.9.2-p136
ruby-1.9.2-p136 - #configuring
ruby-1.9.2-p136 - #compiling
ruby-1.9.2-p136 - #installing
ruby-1.9.2-p136 - updating #rubygems for /home/sam/.rvm/gems/ruby-1.9.2-p136@global
ruby-1.9.2-p136 - updating #rubygems for /home/sam/.rvm/gems/ruby-1.9.2-p136
ruby-1.9.2-p136 - adjusting #shebangs for (gem).
ruby-1.9.2-p136 - #importing default gemsets (/home/sam/.rvm/gemsets/)
Install of ruby-1.9.2-p136 - #complete
sam@sjones:~$ rvm use 1.9.2
Using /home/sam/.rvm/gems/ruby-1.9.2-p136
sam@sjones:~$ ruby -v
-bash: ruby: command not found

我到底该怎么办？我已经试了几个小时了
--编辑--
以下是我的rvm信息输出：

rvm info

 system:

 system:
    uname:       "Linux sjones 2.6.18-194.8.1.el5.028stab070.2 #1 SMP Tue Jul 6 14:55:39 MSD 2010 x86_64 GNU/Linux"
 bash:        "/bin/bash => GNU bash, version 3.2.39(1)-release (x86_64-pc-linux-gnu)"
 zsh:         " => not installed"

 rvm:
 version:      "rvm 1.2.2 by Wayne E. Seguin ([email protected]) [http://rvm.beginrescueend.com/]"

 homes:
 gem:          "not set"
 ruby:         "not set"

 binaries:
 ruby:         ""
 irb:          "/usr/local/bin/irb"
 gem:          ""
 rake:         "/usr/bin/rake"

 environment:
 PATH:         "/usr/local/bin:/usr/bin:/bin:/usr/games:/home/sam/.rvm/bin:/home/sam/.rvm/bin"
 GEM_HOME:     ""
 GEM_PATH:     ""
 MY_RUBY_HOME: ""
 IRBRC:        ""
 RUBYOPT:      ""
 gemset:       ""