Text area posting to php

[Ian Hobson]

Hi All,

I have a site written in php, that I am trying to move onto nginx.

The site works on my test machine = Windows, Apache2.2. and php5.

It does not work on the production machine  (Ubuntu, nginx, php5).

The post of a form with a submit button and a textarea arrives with the 
textarea with no value, and nothing from the button.

The form is

<FORM METHOD="POST" action="question.php?act=Save&amp;subj=2"><table width="100%">
<tr><td width="25%" align="right">Subject : </td><td align="left">Decision Coach</td></tr>
<tr><td><input type="submit" value="Save subject"></td><td> </td></tr>
<tr><td colspan='2' ><textarea COLS="90" rows="35" name="xmlarea" id="xmlarea" >
&lt;questionset title=&quot;Decision Coach&quot;&gt;

lots of content snipped
&lt;/questionset&gt;
</textarea>
</td></tr></table>
</form>

What could be going wrong? How can I diagnose the problem further? 

Regards

Ian