\documentclass{article}
\usepackage{fullpage}
%\usepackage[tight]{subfigure}
%\usepackage[loose,hang]{subfigure}
\usepackage[tight,hang]{subfigure}

\makeatletter
\def\mpt{\@minipagetrue}
\def\mpf{\@minipagefalse}
%\renewcommand{\@thesubfigure}{\subcaplabelfont\thesubfigure\space\itshape}
\makeatother

\fboxsep=-\fboxrule
%\renewcommand{\subcapfont}{\itshape}

\newcommand{\figbox}[1]{%
 \fbox{%
   \vbox to 1in{%
   \vfil
   \hbox to 2in{%
     \hfil
     #1%
     \hfil}%
   \vfil}}}

\begin{document}

Figures wrapped to show any extra spaces introduced in processing the
subfigures.

\begin{figure}%
 \centering
 \fbox{%
   \fbox{\subfigure[Subfigure One.\label{fig:A1}]{%
     \figbox{SUBFIG ONE}}}%
   \hspace{10pt}%
   \fbox{\subfigure[Subfigure Two.\label{fig:A2}]{%
     \figbox{SUBFIG TWO}}}}
 \caption{Two side-by-side figures.}%
 \label{fig:A}%
\end{figure}

\begin{figure}%
 \begin{center}%
   \fbox{\hbox to 4.13837in{\hss\vbox{%
     \fbox{\mpt\subfigure[Subfigure Three.\label{fig:B1}]{%
       \figbox{SUBFIG THREE}}}%
     \hspace{10pt}%
     \fbox{\mpt\subfigure[Subfigure Four.\label{fig:B2}]{%
       \figbox{SUBFIG FOUR}}}\\[-1.5pt]
     \fbox{\subfigure[Subfigure Five.\label{fig:B3}]{%
       \figbox{SUBFIG FIVE}}}%
     \hspace{10pt}%
     \fbox{\subfigure[Subfigure Six.\label{fig:B4}]{%
       \figbox{SUBFIG SIX}}}}\hss}}%
   \end{center}
 \caption{Four figures with specified suppression of extra padding.}%
 \label{fig:B}%
\end{figure}

\begin{figure}
 \centering
 \fbox{%
   \begin{minipage}{4.13837in}%
%\mpf
     \subfigure[Subfigure Seven.\label{fig:C1}]{%
       \figbox{SUBFIG SEVEN}}%
     \hspace{10pt}%
     \subfigure[Subfigure Eight.\label{fig:C2}]{%
     \figbox{SUBFIG EIGHT}}

     \subfigure[Subfigure Nine.\label{fig:C3}]{%
       \figbox{SUBFIG NINE}}%
     \hspace{10pt}%
     \subfigure[Subfigure Ten.\label{fig:C4}]{%
       \figbox{SUBFIG TEN}}%
   \end{minipage}}
   \caption{Four figures with auto fitting in a minipage.}%
   \label{fig:C}%
\end{figure}

\begin{figure}
 \centering
%
 \subfigure[First caption.]{\fbox{Under figure/text}}\quad
 \subfigure[Longer second caption.]{\fbox{Under figure/text}}\\
%
 \subfigure[Third caption.]{\figbox{Under figure/text}}\quad
 \subfigure[Longer fourth caption. longer fourth caption.
            longer fourth caption.]{\figbox{Under figure/text}}
 \caption{Four figures testing caption fitting.}%
\end{figure}

\end{document}