[pdftex] table caption, vertical spacing

[Troy Goodson]

I know that I'm using an old version of pdfTeX, but before I go 
through all the work of upgrading, I'd like someone to please verify 
an issue I'm seeing.  In fact, since I'm very new to (La)TeX, this 
may be expected behavior.

I'm making a table and the vertical spacing between the caption and 
the top border of the table is changing with the width or number of 
columns in the table.  I've copied my pdfTeX code, below.  As 
written, there's a fairly tall space between the table and it's 
caption; however, remove the "&" from "Closest Approach (GMT) & " in 
the first row and the caption will shift down to be just above border.

Is this supposed to happen?  Does it happen with the latest version of pdfTeX?

Thanks,

Troy.

-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

localhost% pdftex -version
pdfTeX (Web2C 7.3.1) 3.14159-0.13d
kpathsea version 3.3.1
Copyright (C) 1999 Han The Thanh, Petr Sojka, and Jiri Zlatuska.
Kpathsea is copyright (C) 1999 Free Software Foundation, Inc.
There is NO warranty.  Redistribution of this software is
covered by the terms of both the pdfTeX copyright and
the GNU General Public License.
For more information about these matters, see the files
named COPYING and the pdfTeX source.
Primary author of pdfTeX: Han The Thanh, Petr Sojka, and Jiri Zlatuska.
Kpathsea written by Karl Berry and others.

-=-=-=-=-=-=-=-=-=-=-=-=-=

\documentclass[12pt]{article}
\usepackage{dcolumn}  \newcolumntype{d}[1]{D{.}{.}{#1}}

\oddsidemargin -0.19in
\textwidth 6.8in

% for centering in tables
\newcommand{\PreserveBackslash}[1]{\let\temp=\\#1\let\\=\temp}

\begin{document}

\let\PBS=\PreserveBackslash % shorthand

\begin{table}\begin{center}
\caption{REV-1 Delivery}\label{tbl:rev1-flyby-params}
\begin{tabular}{|r||>{\PBS\centering\hspace{0pt}}m{1in}%
                    |>{\PBS\centering\hspace{0pt}}m{.9in}%
                    |>{\PBS\centering\hspace{0pt}}m{.9in}%
                    |>{\PBS\centering\hspace{0pt}}m{1.5in}
                       |>{\PBS\centering\hspace{0pt}}m{.9in}|}
\hline
  & B Magnitude (km) & B-Plane Angle (deg) & V-infinity
(km/s) & Time of Closest Approach (GMT) &  \\\hline\hline
Very Early &       3961 &        -22 &       5.79 & 27-Nov-2004 09:15 \\\hline
      Early &       3964 &        -23 &       5.76 & 27-Nov-2004 10:15 \\\hline
       Late &       3939 &        -23 &       5.77 & 27-Nov-2004 10:13 \\\hline
    Nominal &       4057 &        -24 &       5.54 & 27-Nov-2004 14:15 \\\hline
\end{tabular}\end{center}\end{table}


\end{document}