Description:
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According to the PhD specification http://www.docbook.org/tdg5/en/html/imagedata.html, the <imagedata> element has width and depth attributes. However, setting those in php documentation does not take any effect.

Reproduce code:
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<mediaobject>
 <imageobject>
  <imagedata fileref="path to file" width="320" depth="240" />
 </imageobject>
</mediaobject>


Expected result:
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The resultant HTML should have:

<img src="path to file" widht="320" height="240" />

Actual result:
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The result HTML has

<img src="path to file" />