[O] Multiple (natural) languages in a single org-file

Hi

Is there a way to accommodate more than one natural language (e.g.
english and portuguese) in a single org-file?

I often prepare presentations in org-mode and export them using LaTeX's
beamer class. There is usually little text and quite some math.
Often I need to recycle an older presentation but using a different
language, i.e. sometimes I prepare something in english, but later I
will need to recycle it using english.

So far, I get around this by defining a custom LaTeX command:
or

I use this command to write stuff like
* \en{Example: sum of two numbers}\pt{Exemplo: soma de dois números}
\en{Example 1}\pt{Exemplo 1}
$3 = 2 + 1$
\en{Example 2}\pt{Exemplo 2}
$0 = 1 + e^{i\pi}$

I then export to pdf. Switching between languages is a matter of
changing the LaTeX header and exporting again.

Is there a more elegant way of doing this? I would like to be able to
export to HTML and ODT...

Carlos