jquery error: a function is not a function?
<p>How is it possible that, being 'colonna' a simple string:</p>

<pre><code>$('td.' + colonna).css('background-color','#ffddaa');
</code></pre>

<p>works correctly highlighting the background of the interesting cells, and:</p>

<pre><code>$('td.' + colonna).contains('Catia').css('background-color','#ffddaa');
</code></pre>

<p>produces the error: "$('td.' + colonna).contains is not a function"?</p>

<p>Someone has an idea?</p>

<p>Thanks!</p>
