# Strange character when using listings package

I'm seeing an odd character like a very flat U, where there should be a space, with the listings package. See example below. Does anyone have any idea why this is happening, or how to get rid or work around it?

\documentclass{standalone}
\usepackage{underscore}
\usepackage{listings}
\usepackage[usenames,dvipsnames, rgb, svgnames, x11names]{xcolor}
% Text layout
\topmargin 0.0cm
\oddsidemargin 0.5cm
\evensidemargin 0.5cm
\textwidth 16cm
\textheight 21cm
\lstnewenvironment{cmd}[1][]{%
\lstset{language=sh, backgroundcolor=\color{LightSteelBlue1}, #1}}
{}

\begin{document}
\begin{cmd}[caption=Configuration file section including filters]
[affy6]
[...]
[[hapmap]]
phenofiles = "data/Hapmap6.0/Pheno/hapmappheno_909.csv",
genofile = "/data/snppy/Hapmap6.0/Geno/birdseed-v2.calls.txt"
anno_filter = "chromosome = 5"
some_other_stuff = "foo = bar"
\end{cmd}
\end{document}


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Please try to load \usepackage[T1]{fontenc} and maybe the font berano or so –  Marco Daniel May 3 '12 at 6:18
@MarcoDaniel: Why? –  Faheem Mitha May 3 '12 at 14:38

By default, listings shows spaces as a "squat-u" as part of strings (between quotes). Add the option showstringspaces=false to your list of \lstset options to remove this.
@FaheemMitha: In terms of programming, code sometimes have whitespace for readability. However, in terms of strings (typically used to produce output or assigned to variables), it may be very important if you use one or two spaces, say. TeX is similar in the sense that it gobbles spaces in code as needed, but not with string comparisons. For example: \def\strA{this that}\def\strB{this  that}\ifx\strA\strB true\else false\fi will yield false, while \strA and \strB will typeset exactly the same in the output. –  Werner May 3 '12 at 14:06