Description:
------------
I cant seem to change the value of an array entry in a simple xml object if I use a variable for an index.
But it changes OK if I use a constant.


Reproduce code:
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<?php
$xmlstr = "<root><people><name>gerry</name><name>barbara</name></people></root>";
$xml = simplexml_load_string($xmlstr);
$i = 0;
$xml->people->name[$i] = "gerry changed";  // sorry, gerry doesnt change if variable is used as index (bug?)
echo $xml->people->name[0];
echo "<br>";
$xml->people->name[0] = "gerry changed";  // gerry does change is a constant is supplied
echo $xml->people->name[0];

?> 


Expected result:
----------------
gerry changed 
gerry changed 



Actual result:
--------------
gerry
gerry changed 
<the first gerry should be gerry changed>