span tags stripped when importing from MT 2.661 to WP 2.02

I set up a new wordpress blog with WP 2.02, exported from my MT 2.661 blog to WP 2.02 using the UI. Went ok except that my photos in MT are surrounded by span tags, like so:

<span style="float:right; padding: 3px;">
<IMG SRC="http://www.thebishop.net/geodog/archives/images/supernova_sm.jpg" WIDTH="240" HEIGHT="180" BORDER="0" ALT="Supernova party">

</span>


All the information in the span tags has been stripped by the importer. Is there any way to avoid / fix this?

Thanks in advance