# Invalid right aligned chapter and section titles

I'm trying to write a bidirectional (English/Hebrew) document in xelatex and polyglossia. For some reason, when I enable Hebrew as a secondary language, all the chapter and section titles become right-aligned, even when they are in English. Do you know why this happens?

Here's a simple example:

\documentclass{book}
\usepackage{polyglossia}
\setdefaultlanguage{english}
\setotherlanguage{hebrew}

\begin{document}
\chapter{Hello world}
\end{document}


And this is how it looks:

-
It is because you are using an ancient version of bidi package. Please update your TeX distribution. The current version of bidi package is 11.158. –  Vafa Khalighi Jun 21 '12 at 6:01
Thanks. I had no idea Ubuntu lagged so much behind. Installing the latest tex-live now... –  haggai_e Jun 22 '12 at 5:25