🚀 go-pugleaf

I'm perhaps still a newbie in LaTeX and I've got
a problem that I can not solve (and I try hard).

Here the problem :

I've got a first file, say misc.tex which will contains a lot of data like

%%%%%%%%%%% begin of misc.tex
\input{header}

\ACOL{A1}
\BCOL{A2}
\CCOL{A3}
\makeform

\ACOL{B1}
\BCOL{B2}
\CCOL{B3}
\makeform

\input{tail}
\end{document}
%%%%%%%%%%% end of misc.tex

the file header.tex will contain instructions to present the data, say for instance 

%%%%%%%%%%% begin of header.tex
\documentclass{article}

\def\RESET{%
	\gdef\acol{}%
	\gdef\bcol{}%
	\gdef\ccol{}}%

\def\ACOL#1{\gdef\acol{#1}}
\def\BCOL#1{\gdef\bcol{#1}}
\def\CCOL#1{\gdef\ccol{#1}}

\def\makeform{
	\acol & \bcol & \ccol \\ \hline
	\RESET}

\begin{document}

\begin{tabular}{|c|c|c|} \hline
COL 1 & COL 2 & COL 3 \\ \hline \hline
%%%%%%%%%% end of header.tex

the file tail.tex contains additional stuff (in this example "\end{tabular}").


What I want to do is to process a big file misc.tex by different way by changing
only the definition of \makeform in header.tex.

But by running latex (This is TeX, Version 3.1415 (C version 6.1), LaTeX2e <1995/06/01> patch level 3)
I've got the following output :

     -------------------------
     | COL 1 | COL 2 | COL 3 |
     -------------------------
     |    A1 |  A2   |  A3   |
     -------------------------
     |    B1 |  B2   |  B3   |
     -------------------------
     |       |

instead of what I expected :

     -------------------------
     | COL 1 | COL 2 | COL 3 |
     -------------------------
     |  A1   |  A2   |  A3   |
     -------------------------
     |  B1   |  B2   |  B3   |
     -------------------------

There are two problems:

1/ the first column is NOT centered, but somewhat to the right
2/ there are two extra vertical lines at the bottom of the table

What is wrong ?

Thank you in advance for any help.

Gregoire

 -------------------------------------------------------------------------
 Gregoire MALANDAIN                                   Tel: +33 93 65 79 26
 I.N.R.I.A. Sophia                                    Fax: +33 93 65 76 69

 http://www.inria.fr/epidaure/personnel/malandain/malandain.html
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