Rounded corners on fieldset borders

Hi!

I have this

input[type=text],
input[type=submit],
fieldset {
	border:rgb(240,240,240) thin solid;
	-webkit-border-radius: 5px; -moz-border-radius: 5px; border-radius: 5px;
	padding: 2px;
}

in my code and all elements are nicely rounded except the fieldset in IE10/9.

how do I make rounded borders on fieldsets?