I have the following markup. I would like there to be a 5px border surrounding the "content" (see the inner splitter) which should fill the available space. I have the page containers set to height/width = 100%. For some reason the border disappears off the right and bottom edge. I thought this might be the old IE 6 box model issue, but this occurs in IE7 and Firefox 3 as well. Can anyone tell me what I'm doing wrong?