listings breaklines not working [duplicate]

Possible Duplicate:
How to deal with very long lines that do not contain spaces?

When I use the listings package with breaklines, it doesn't seem to break lines properly if there is no whitespace. For example:

\documentclass{article}
\usepackage{listings}
\lstset{breaklines=true, breakatwhitespace=false}
\begin{document}
\begin{lstlisting}[frame=single]
blah blah
blah blah
jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj
\end{lstlisting}
\end{document}


This gets rendered like this:

Is there some way to get long lines like this to break? I thought setting breakatwhitespace to false would fix this.