** leading commas in code blocks
   :PROPERTIES:
   :DATE:     2011-09-06
   :END:
#+begin_src r :exports code
  a <- c(1
         , 2
         , 3)
#+end_src

#+begin_src org :exports code
  ,this one will have commas removed
  ,#+begin_src R
  ,  a <- c(1
  ,         , 2
  ,         , 3)
  ,#+end_src
#+end_src