border radius htc not working in ie8 .. joomla1.5 puritty ii templates

I had using htc file...

but no use in ie8

anybody knows the solution ...plz post here

.rounded-corners {
-moz-border-radius: 20px;
-webkit-border-radius: 20px;
-khtml-border-radius: 20px;
border-radius: 20px;
}

.rounded-corners {
behavior: url(/css/border-radius.htc);
border-radius: 20px;
}