The idea is to insert \strut with appropriate height and depth in the template of the table. I'm not a LaTeX user but you would do something like
{\offinterlineskip
\halign{\strut\vrule\enspace\hfil #\hfil\enspace&\vrule\enspace\hfil # \hfil\enspace\vrule\crcr
\multispan2\hrulefill\cr
Vafa&Shahrzad\cr
\multispan2\hrulefill\cr}}
in Plain TeX. The first line is simply where we define the template of the alignment. In LaTeX,
the template is predefined so you have to redefine it or use some other package that
allows you to define your \halign template. The actual height and depth of \strut has to be equal or greater than the maximum height and depth. The default value in Plain TeX is
8.5pt height and 3.5pt depth.
