Why does pdflatex/dinbrief produce a US letter page for this input?

Question

I want to write a simple letter using the dinbrief class but cannot get it to produce a DIN A4 page. The minimal example is this:

\documentclass[11pt,a4paper]{dinbrief}
\usepackage{german}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{eurosym}
\begin{document}
\subject{Some subject}
\backaddress{Me, some address}
\signature{Me again}
\Datum{Someplace}
\address{my name\\someplace\\some city}
\begin{letter}
{Other guy\\
his city}
\opening{Dear pdfLaTeX,}

why don't you produce the proper page size?

\closing{Kind regards}
\end{letter}
\end{document} 

This produces a US letter sized document when I run pdflatex document from the terminal. I run ubuntu 12.04 with texlive-full packages installed and updated. I would assume the a4paper option in the header is pretty unambiguous...

Am I missing something obvious?

Answer 1

Quite a lot of old classes (e.g. article or your dinbrief) don't set the pdf sizes. An option like a4paper sets only things like the TeX \paperwidth, the linewidth and similar lengths.

You will have to insert the necessary command yourself. For pdflatex this is

\pdfpagewidth=\paperwidth
\pdfpageheight=\paperheight

For latex/dvips you need a \special{...}.

You can also load one of the packages graphicx, or hyperref, or geometry which will set the pdf lengths for you.

Btw: The people who can't reproduce your problem probably have a4paper as default. In this case they would see your problem if they used e.g. the option letterpaper.

Answer 2

With Ubuntu 12.10 the default paper size of pdflatex can be changed by running

sudo paperconfig -p a4

This changes some configurations including /etc/papersize, which was set to letter. Beware that there is also a command named paperconf, which does not change anything.