Hi I was trying a gnuplot source block, and was stricken by "No org-babel-execute function for gnuplot!" when I tried to execute the block. I made sure the variable org-babel-load-languages contained (gnuplot . t) , so I was quite puzzled.
It turns out that I needed to explicitly add (require 'ob-gnuplot) to my .emacs file. According to the documentation, this line should not be needed for org-mode 8.03 (my current version). It this a bug in the documentation? Cheers, Carlos