xeCJK and quotation marks

In a document mostly in English and Sanskrit, I would like to display a few short strings in Chinese, a language apparently not supported by polyglossia, which I normally use for language switching commands. It appears that the xeCJK package is the recommended option for that. However, it seems to be messing up quotation marks:

documentclass{article}
usepackage{xeCJK}
setCJKmainfont{Droid Sans Fallback}
begin{document}
“test” ``test''
end{document}

Now, this is probably a feature I don’t understand, but the documentation is in Chinese. I wonder if it can be disabled? I would rather not want to switch back all my quotation marks to `` and ''.