CSS !important not working

I have the following code and for some reason the !important qualifier isn't working.

<div style="font-family : calibri; font-size: 20pt !important;">
  <ul>
    <li>
      <span style="font-size: 11px;">
        <span style="font-size: 11px;">
          Honey Glazed Applewood Smoked Spiral Ham 
        </span>
        <span style="font-size: 11px;">
          Served with Dijon Honey Mustard and Turkey Roulade
        </span>
      </span>
    </li>
  </ul>
</div>

Give the <div> an id and then add this rule to your CSS stylesheet (or in a <style> tag if you don't want to change the style sheet):

#your_div_id span {font-family : calibri; font-size: 24px !important;}

!important in CSS allows the author to override inline styles (since they have a higher precedence than style sheet styles normally). It doesn't automatically make the style marked !important override everything else.