%% 
%%  A DANTE-Edition example
%% 
%%  Example 02-01-15 on page 26.
%% 
%%  Copyright (C) 2010 Herbert Voss
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%% 
%%  See http://www.latex-project.org/lppl.txt for details.
%% 
%% 
%% ==== 
% Show page(s) 1
%% 
\documentclass[]{article}
\pagestyle{empty}
\setlength\textwidth{129.70511pt}
\setlength\parindent{0pt}

\usepackage{array}

\begin{document}
\begin{tabular}{|l!{\vrule width 3pt}l|c|l|l|}\hline
L & L & C & L & L\\
LL&\multicolumn{3}{!{\vrule width 3pt}c|}{CCC} & L\\\hline
\end{tabular}
\end{document}

.
