Is something like this what you want?
<table cellspacing="0" cellpadding="0">
<tr>
<td class="left"> </td>
<td class="center">Your content goes here</td>
<td class="right"> </td>
</tr>
</table>
styled such that
table {
/* the table takes up all the space */
width: 100%;
}
td.center {
/* there is one container column */
width: 1000px;
text-align: center;
color: white;
background-color: black; /* some fixed background color */
}
/* and two columns on the side which fade to some other color, in the respective directions */
td.left {
background: -webkit-gradient(linear, left, right, from(white), to(black));
background: -webkit-linear-gradient(left, white, black);
background: -moz-linear-gradient(left, white, black);
background: -ms-linear-gradient(left, white, black);
background: -o-linear-gradient(left, white, black);
background: linear-gradient(left, white, black);
}
td.right {
background: -webkit-gradient(linear, right, left, from(white), to(black));
background: -webkit-linear-gradient(right, white, black);
background: -moz-linear-gradient(right, white, black);
background: -ms-linear-gradient(right, white, black);
background: -o-linear-gradient(right, white, black);
background: linear-gradient(right, white, black);
}
You can try this example here: http://jsfiddle.net/qvum4/1/
UPDATE
However, if you don't have a specific reason to use tables, and you only want to achieve this effect, you shouldn't use tables.
There are a few jQuery gradient plugins around, that you can try to use.
Of you could develop a custom jQuery solution, in order to keep all the styling gibberish outside of the markup.
Try this example here: http://jsfiddle.net/YnUpY/1/