+@item :lang
+The language that the font should support. The value should be a
+symbol whose name is a two-letter ISO-639 language name. On X, the
+value is matched against the ``Additional Style'' field of the XLFD
+name of a font, if it is non-empty. On MS-Windows, fonts matching the
+spec are required to support codepages needed for the language.
+Currently, only a small set of CJK languages is supported with this
+property: @samp{ja}, @samp{ko}, and @samp{zh}.
+