seems like I found the solution, see

* Org Export Latex Listings:
...
   If you want to use this, you also need to make LaTeX use the
   listings package, and if you want to have color, the color
   package.  Just add these to `org-export-latex-packages-alist',
   for example using customize, or with something like

     (require 'org-latex)
     (add-to-list 'org-export-latex-packages-alist '("" "listings"))
     (add-to-list 'org-export-latex-packages-alist '("" "color"))

maybe this should be mentioned in the tutorial.

Actually I don't understand why this flag doesn't automatically include the
latex-package listings.

Nevermind the other problem with BEAMER_FRAME_LEVEL, it was a consequence of
trying to solve the former one.

Cheers
  Rolf

2011/8/6 LanX <lanx.perl@googlemail.com>

> ECM?
>
> The worg tutorial has an example using #+begin_src which should be
> translated into \begin{lstlisting} environments in latex.
>
> namely:
>
> #+begin_src octave
> A = [1 2 ; 3 4]
> b = [1; 1];
>
> x = A\b
> #+end_src
>
> But when I check the corresponding latexcode (C-c C-e L) the  necessary
> package is not imported, namely   "\usepackage{listings}"
>
> I was able to solve the other problem with BEAMER_FRAME_LEVEL  adding
> "\subsection{%s}" to Org-Export-Latex-Classes.
>
> I'm using  gnu-emacs 23.1.50.1.
>
> It seems like some auto-configurations of the latex-classes are not
> initialized.
>
> If I'm the only one experiencing this problem I will try to set up a new
> emacs instance to test it.
>
> Cheers
>   Rolf
>
> 2011/8/6 Sebastien Vauban <wxhgmqzgwmuf@spammotel.com>
>
>> Hi LanX,
>>
>> LanX wrote:
>> > maybe I'm missing something but the examples in
>> >
>> > http://orgmode.org/worg/org-tutorials/org-beamer/tutorial.html
>> >
>> > don't seem to work with a normal org-mode 7.7 installation.
>> >
>> > For instance  needed to add       \usepackage{hyperref} in
>> > Org-Export-Latex-Classes to make #+begin_src work.
>> >
>> > Are the settings of
>> >
>> http://emacs-fu.blogspot.com/2009/10/writing-presentations-with-org-mode-and.htmlnecessary
>> > to use this tutorial?
>> >
>> > Also
>> > #+BEAMER_FRAME_LEVEL: 3
>> > doesn't seem to work for me... no subsections are generated.
>>
>> Could you send us an ECM (complete, but... minimal example) that allows us
>> to
>> reproduce the above problems?
>>
>> Best regards,
>>  Seb
>>
>> --
>> Sebastien Vauban
>>
>>
>>
>