CSS Validation: "Parse Error [empty string]" -

i have been trying validate css, , following lines continually return error parse error [empty string]

.content { width:80%; text-align:center; margin-left:auto; margin-right:auto;  max-width:400px; border-width:4px; border-style:solid; border-color:#339900;  padding:5px; margin-top:10px; margin-bottom:10px; border-radius:20px;  background-color:#ccffcc; } #side_link { position:fixed; bottom:5px; right:-4px;  background-image:url('img/fruitfullogo.png'); height:29px; width:22px;  border-style:solid; border-width:2px; border-bottom-left-radius:5px;  border-top-left-radius:5px; border-color:#f90; background-color:#ff9; } #side_link:hover { background-image:url('img/fruitfullogo_over.png'); } 

am missing obvious or obscure?

apparently, border-radius throwing parse error [empty string] bug in w3c css validator.

see http://www.w3.org/bugs/public/show_bug.cgi?id=11975 .