Remove Minus signs in XML inside a tag
<p>I'm trying to use preg_replace to replace - to _ between Tags only</p>

<p>Test string normaly received in the header response of a POST request</p>

<pre><code>  $response['body'] = &lt;&lt;&lt;STR
    &lt;?xml version="1.0"?&gt;
        &lt;tracking-events&gt;
        &lt;tracking-event&gt;
        &lt;type&gt;DELIVERED&lt;/type&gt;
        &lt;time&gt;2012-12-04T11:45:08.554+0200&lt;/time&gt;
        &lt;tracking-id&gt;AB10000&lt;/tracking-id&gt;
        &lt;/tracking-event&gt;
        &lt;/tracking-events&gt;
    STR;
</code></pre>

<p>Can you help me out changing - to _ and keep the date format as is</p>

<pre><code>$response['body'] = &lt;&lt;&lt;STR
&lt;?xml version="1.0"?&gt;
    &lt;tracking_events&gt;
    &lt;tracking_event&gt;
    &lt;type&gt;DELIVERED&lt;/type&gt;
    &lt;time&gt;2012-12-04T11:45:08.554+0200&lt;/time&gt;
    &lt;tracking_id&gt;AB10000&lt;/tracking_id&gt;
    &lt;/tracking_event&gt;
    &lt;/tracking_events&gt;
STR;
</code></pre>
