Code: Select all
\documentclass[]{article}
\usepackage{hhline}
\begin{document}
\begin{tabular}{|c|c|}
\hhline{==}
one & two \\
\hhline{--}
three & four \\
\hhline{==}
\end{tabular}
\end{document}
How can I get a double line and still use colortbl?