I feel like a noob for asking this but I can't seem to figure out why I am having a 1px gap in the bottom border only for my tables on a website. It only shows when I attempt to use a border at the bottom of a table or a hovered row.

Due to client privacy I can not send a link to the test site, but here is an image of the issue:

If you look at the column divider and follow that down, you can see there is a white spot at the bottom of the selected row as well as the border-bottom of the table. I also see one at the top in Chrome.

CSS attached to tables:

body {
    font-family: Arial,Helvetica,sans-serif;
    font-size: 12px;
table{margin-bottom:21px;border-bottom:1px solid #bbb;}
        height: 25px;
        line-height: 25px;
        border-right: 1px solid #fff;
        text-align: left;
        padding: 0 8px;
        color: #555;
            border: 1px solid #bbb;
            background: #ffffff; /* Old browsers */
            background: -moz-linear-gradient(top,  #ffffff 0%, #e2e2e2 100%); /* FF3.6+ */
            background: -webkit-linear-gradient(top,  #ffffff 0%,#e2e2e2 100%); /* Chrome10+,Safari5.1+ */
            filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#ffffff', endColorstr='#e2e2e2',GradientType=0 ); /* IE6-8 */
            -webkit-box-shadow:  1px 0px 2px 1px rgba(0, 0, 0, .17);
            box-shadow:  1px 0px 2px 1px rgba(0, 0, 0, .17);
            cursor: pointer;
tr.hover td{background:none !important;border:none !important;}
th.last,td.last{border-right:none !important;}
And here is the table itself:
<table border="0" cellpadding="0" cellspacing="0" width="100%">
			<th class="last">Description</th>
				<td class="last">Fractured tibia</td>
			<tr class="hover">
				<td class="bg_blue">01/12/2012</td>
				<td class="bg_blue last">Diagnosed Type II Diabetes</td>
				<td class="last">Heart Attack</td>
I've tried adding a border to the td and it also stops at that spot. At this point I've exhausted my ideas and my Google Fu is not pulling up anything. I did not grow up in the age of tables so not sure if there are hidden nuggets out there that would help this issue.

Any help is greatly appreciated.