natbib and hyperref for (Author, Year) style produces two links

I am using the bioinfo style with natbib and hyperref, using the (Author, Year) style citations. pdflatex produces two link boxes for each citation: one for the Author and one of the Year. I would prefer to get a single link for the entire [(Author, Year)] rather than ([Author], [Year]). I can turn off PDF link boxes and uses colors instead to somewhat improve the appearance of this, but I'd still prefer to just have a single link.

Thanks in advance for any suggestions on how to fix this.

Here is a minimal example:

\documentclass{article}\usepackage{natbib}\usepackage{hyperref}\begin{filecontents}{\jobname.bib}@book{adams80,  title = {The Restaurant at the End of the Universe},  author = {Douglas Adams},  series = {The Hitchhiker's Guide to the Galaxy},  publisher = {Pan Macmillan},  year = {1980}}\end{filecontents}\begin{document}A theory about the inexplicability of the Universe has been proposed by \citet{adams80}.\bibliographystyle{plainnat}\bibliography{\jobname}\end{document}