CSS Validator bug due to css size?

Hi,
we have a problem with the following css validation:

http://www.provincia.le.it/html/portal/css.jsp

If we try to validate using "*Validate by URI*", we get a "*Parse Error 
[empty string]*";
If we try to validate using "*Validate by direct input*" by pasting the 
output of the browser for the uri 
/http://www.provincia.le.it/html/portal/css.jsp/ we get "*Validation OK*";
If we try to validate using "*Validate by file upload*" by choosing a 
file on local computer that is the output of the command /'wget 
http://www.provincia.le.it/html/portal/css.jsp'/ we get "*Validation OK*";

Can you confirm that this is a bug of the validator?

We wait for your help.

Best Regards