DOCBOOK-APPS: Image width and height attribute for HTML

I am using <inlinegraphic> to specify an image in my xml file.  When
converted to HTML, there are no height attributes.

I would like: <inlinegraphic fileref="images/logo.gif"/> to be translated to

<img src="images/logo.gif" width="55" height="54">

I see that the inlinegraphic tag has a width attribute, but not a height.
How do I get these values in my tags?  Either I am using the wrong tag or I
need to customize the xsl?

Maggie