That feature is still under active development.  Currently, the Word 
importer includes code to support the following file formats:
  Word 97
  Word 95
  Word 6.0
AFAIK, the Word 97 support has been around the longest and thus had gotten 
the most testing.  The others have been added more recently, so problems 
found there should be reported either through Bugzilla or directly to the 
developer list.  (As always, test documents which zero in on the problem are 
especially helpful.)  
I don't know anything about the quality of WordPad's exporter, so that may 
be another potential source of problems.  
Paul