[O] Latex "Missing number, treated as zero."

[Ian Barton]

This is a Latex problem, but I am hoping someone here can trow some 
light on it. I was trying out the Koma Letter Export script. I get the 
following error when trying to create a pdf from the "Simple letter 
example".

)) (/usr/share/texmf/tex/latex/koma-script/DIN.lco)
(/usr/share/texmf-dist/tex/generic/babel/babel.sty
(/usr/share/texmf-dist/tex/generic/babel-english/english.ldf
(/usr/share/texmf-dist/tex/generic/babel/babel.def)))
! Missing number, treated as zero.
<to be read again>

Chopping down the text file to the minimal:

\documentclass{scrlttr2} \usepackage[english]{babel}  [NO-DEFAULT-PACKAGES]


\begin{document}


\end{document}

still gives the error. However, if I remove [NO-DEFAULT-PACKAGES] I 
don't get the error. I spent some time Googling, but can't find anything 
helpful.

latex --version gives:

pdfTeX 3.1415926-2.5-1.40.14 (TeX Live 2013/Arch Linux)
kpathsea version 6.1.1
Copyright 2013 Peter Breitenlohner (eTeX)/Han The Thanh (pdfTeX).
There is NO warranty.  Redistribution of this software is
covered by the terms of both the pdfTeX copyright and
the Lesser GNU General Public License.
For more information about these matters, see the file
named COPYING and the pdfTeX source.
Primary author of pdfTeX: Peter Breitenlohner (eTeX)/Han The Thanh (pdfTeX).
Compiled with libpng 1.6.6; using libpng 1.6.7
Compiled with zlib 1.2.8; using zlib 1.2.8
Compiled with poppler version 0.24.2


Ian.