website and keyword vs. keywords

Hi,

my name is Thomas Porschberg and I maintain a small website,
http://randspringer.de , created with website 2.6.0 and docbook
xsl-stylesheets.

I observed the following behavior:
When I create in the source XML some <keywords>chess ....</keywords>
in the resulting HTML-page I see:

<meta name="keyword" content="chess... >

When I look at the examples at 
http://www.w3.org/TR/REC-html40/struct/global.html#edef-META

I see something like:

<META name="keywords" content="corporate,guidelines,cataloging">
                   ^

Is it a bug in the stylesheets or do I misunderstand something here ?

Best regards and thank you for website !
Thomas

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