Using Position Relative/Absolute within a TD?

This is because according to CSS 2.1, the effect of position: relative on table elements is undefined. Illustrative of this, position: relative has the desired effect on Chrome 13, but not on Firefox 4. Your solution here is to add a div around your content and put the position: relative on that div instead of the td. The following illustrates the results you get with the position: relative (1) on a div good), (2) on a td(no good), and finally (3) on a div inside a td (good again).

<table>
  <tr>
    <td>
      <div style="position:relative;">
        <span style="position:absolute; left:150px;">
          Absolute span
        </span>
        Relative div
      </div>
    </td>
  </tr>
</table>