malformed URL that cannot be parsed by the server

I have recently started validating my pages for CSS errors and I think
the W3C validator is great.
 
To let users see (and check for themselves) I have placed the W3C CSS
logo at the bottom of all my pages using the referer URL recommended on
your site and it works fine.
http://jigsaw.w3.org/css-validator/check/referer
 
However, when I use the W3C link checker it returns the following error:
 
 <http://jigsaw.w3.org/css-validator/check/referer>
http://jigsaw.w3.org/css-validator/check/referer 

What to do: Usually the sign of a malformed URL that cannot be parsed by
the server.


Response status code: 400
Response message: Bad Request 

Line: 406
 
Is there anything that can be done about this or am I doing something
wrong? It has been suggested to me that this is a fault on the W3C
server.
 
Your assistance would be appreciated.
 
http://www.web-wise-wizard.com/
 
 

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