Span inside td does not override td style

Span inside td does not override td style

I have a span tag inside a td. The td has a class with CSS to set the
text-decoration to underline, while the span sets the text-decoration to
none. I expect the text inside the span to not be underlined, but for some
reason it is. Why?
Example at http://jsfiddle.net/mfV5V/2/
<table>
<tr>
<td class="u">
<span class="no-u" style="text-decoration: none
!important;">My Text</span>
</td>
</tr>
</table>