IE doesn't support outline-offset so another solution would be to create 2 div tags, one nested into the other one. The inner one would have a border and be slightly smaller than the container.
.container {_x000D_
position: relative;_x000D_
overflow: hidden;_x000D_
width: 400px;_x000D_
height: 100px;_x000D_
background: #000000;_x000D_
padding: 10px;_x000D_
}_x000D_
.inner {_x000D_
position: relative;_x000D_
overflow: hidden;_x000D_
width: 100%;_x000D_
height: 100%;_x000D_
background: #000000;_x000D_
border: 1px dashed #ffffff;_x000D_
}
_x000D_
<div class="container">_x000D_
<div class="inner"></div>_x000D_
</div>
_x000D_