# Adobe Reader and xcolor within a table breaks the line render

I'm using the xcolor package to colour the top row in a table. This is displayed properly using PDF viewers such as Preview or Skim (Mac). But using Adobe Reader 10.1.3 (either Windows or Mac) doesn't display the table line properly.

But removing the colouring for the table fixes it. Here is the example that works as expected:

\begin{table}
\caption{Table showing Feature 5's Functional Tests}
\hspace*{-0.5in}
\begin{tabular}[h!]{|p{0.6cm}|p{4cm}|p{5cm}|p{4cm}|p{1.5cm}|}
\hline
{\bf Test ID } & {\bf Task } & {\bf Expected} & {\bf Actual} & {\bf Outcome} \\
\hline
5.1 & Something &  Something & Something &  Success \\
\hline
5.2 & Something &  Something & Something &  Success \\
\hline
5.3 & Something &  Something & Something &  Success \\
\hline
5.4 & Something &  Something & Something &  Success \\
\hline
\end{tabular}
\end{table}


And here is the example with a coloured row:

\begin{table}
\caption{Table showing Feature 5's Functional Tests}
\hspace*{-0.5in}
\begin{tabular}[h!]{|p{0.6cm}|p{4cm}|p{5cm}|p{4cm}|p{1.5cm}|}
\hline
\rowcolor{gray!25}
{\bf Test ID } & {\bf Task } & {\bf Expected} & {\bf Actual} & {\bf Outcome} \\
\hline
5.1 & Something &  Something & Something &  Success \\
\hline
5.2 & Something &  Something & Something &  Success \\
\hline
5.3 & Something &  Something & Something &  Success \\
\hline
5.4 & Something &  Something & Something &  Success \\
\hline
\end{tabular}
\end{table}


Removing the \rowcolor{} command replacing it with \cellcolor{} creates the same view. Any idea how to fix this?

I've tried printing it out of Adobe and the lines print fine, but as this will be read on as a soft copy it's pretty important. Here is a gallery to show the out of of the LaTeX code.

Any idea how to fix this?

-

\setlength\arrayrulewidth{0.6pt}