becomes  

Thanks for a very useful module!

The author of the blog I'm importing was fond of using   which was appearing in the node body as  

I preserved the author's original code by adding this to function wordpress_migrate_import_form_submit:

$wxr_string = str_replace(' ', ' ', $wxr_string);

Don't know that this is the best fix, but it was quick and it worked.

Patch file attached, includes comments delimiting my change.