Aligning comments that break in several lines?

Question

Possible Duplicate:
How to align comments with lstlistings?

I want to include Matlab code with long comments. The next MWE shows that it is achieved by using the listings package. However I would like these long comments to be aligned when they are split in several lines, i.e. I want to align all the % in my final output. Note that the comments need not to be aligned in the original listing!

\documentclass{article}

\usepackage{fullpage}

\newcommand\sample{Some text to experiment with line numbering. }

\usepackage{listings}
\lstset{language=Matlab}
\lstset{tabsize=2}
\lstset{
  language={Matlab},
  keepspaces=true,
  basicstyle=\small,
  xleftmargin=\parindent,
  xrightmargin=\parindent,
  frame=single,
  framesep=2mm,
  framerule=0pt,
  frame=single,
  columns=flexible}

\lstset{postbreak=\raisebox{0ex}[0ex][0ex]{\ensuremath{\%}}}
\lstset{breaklines=true, breakindent=10cm, breakatwhitespace=true}

\begin{document}

\sample \sample \sample \sample \sample 

\begin{minipage}[c]{\textwidth}

\begin{lstlisting}[language=Matlab, linewidth=15cm]
clear all; clc; close all                                     % Clear all variables, close all figures and clear workspace
Data=randi([2 7], 1, 20)                                % Generate a random sample with 20 elements
Table = [DataValue', Frequency', RelFreq, CumRelFreq]   % Generate a table with the previous results

\end{lstlisting}

\end{minipage}

\end{document}

Could someone let me know if this is possible?