border-image-repeat incorrect display

[cc0800]

When setting the value of border-image-repeat to repeat, round, etc, the middle bars of a border-image do not correctly repeat only the valid middle image segment but rather repeat across the entire image.

CSS:

div.bordertest {
	width: 200px;
	height: 200px;
	background: #404040;
	border: 8px solid #440000;
	box-sizing: border-box;
	border-image: url('border-tester.png') 8;
	border-image-repeat: repeat;
}

Border image [24x24 pixels, sliced into 8x8 corners]:

Appearance in Ultralight:

Appearance in Firefox or Chrome (desired output):