On a source like this:

 
 class K
   def initialize(myval)
     @foo= @foo * 2
     return myval
   end
   def superbaz
     @foo= @foo * 2
   end
 end
 
extracting  "@foo= @foo * 2"  as "foo_doubler" results in:
 
 
 class K
   def foo_doubler()
     @foo= @foo * 2
   end
   def initialize(myval)
     foo_doubler()
     return myval
   end
   def superbaz
     @foo= @foo * 2
   end
 end
 
 
so just an occurrence gets changed, while the refactoring could extend 
to the second one. 
The refactoring is called by selecting the string and selecting the refactor->extract_method menu



The problem happens with the freeride 0.9 tar.gz file, on windows xp pro with the oneclick-installer for 1.8.2 (both
rc9 and rc10)

(note: there is no 0.9 choice in the group box for PR, yet)