Hey,
I have an elisp source block that builds a table from some computation. When trying to #+CALL that block, the table header (before the 'hline) is simply not shown. Here is a simple reproduce on my system:

----------------------------------------------
#+name: test
#+BEGIN_SRC elisp
(list (list 'a 'b 'c 'd) 'hline (list 1 2 3 4) (list 3 4 5 6))
#+END_SRC

#+RESULTS: test
| a | b | c | d |
|---+---+---+---|
| 1 | 2 | 3 | 4 |
| 3 | 4 | 5 | 6 |


#+CALL: test()
#+RESULTS:
| 1 | 2 | 3 | 4 |
| 3 | 4 | 5 | 6 |

#+CALL: test() :results raw
#+RESULTS:
((1 2 3 4) (3 4 5 6))
----------------------------------------------

What am I doing wrong? ;)

Thanks,
Shlomi

Emacs  : GNU Emacs 25.1.50.1 (x86_64-apple-darwin13.4.0, NS appkit-1265.21 Version 10.9.5 (Build 13F1603))
 of 2016-03-17
Package: Org-mode version 8.3.4 (release_8.3.4-686-g18b766 @ ~/org-mode/org-mode/lisp/)