Ruby access denied to system scripts (aka command not found)
===

I use RVM to manage many installations of Ruby on my computer (Mac OS X Snow Leo powered). My default Ruby is 1.9.3-p194.

In one of my old Rails applications, that I still develop, I use Ruby EE 1.8.7. It is selected via `.rvmrc` file, so whenever I get into that directory I receive a message:
 
      Using /Users/rocket/.rvm/gems/ree-1.8.7-2012.02 with gemset mdev

The problem is that in application mentioned above I use some system scripts and execute them via backticks( ` `` `). Unfortunately I get error: ` command not found: /bin/pidof process_name `.

I tried execute that script via irb and behaviour was exactly the same:

      1.8.7 :001 > puts `/bin/pidof Finder`
      (irb):1: command not found: /bin/pidof Finder
      => nil 

By coincidence I ran `irb` in my home folder and everything worked fine:

      1.9.3-p194 :001 > puts `/bin/pidof Finder`
      247 
      => nil 

Now I am incredibly confused and have no idea how to manage that.
