I have a library of documents arranged by topic, which are folders, and I wish to associate an Author property with each uploaded file.  Author is a text box on the form that posts to this DTML method and topic is passed in the querystring.  The following DTML works great with Netscape, Mozilla, and Opera but fails with IE on line 3 with a Key error.  Any suggestions on how to make this browser independent?  (I know, tell people to stop using IE was my first thought.)   I am suspicious that IE is not handling _.getitem(file.filename,0) properly. 
 
<dtml-with expr="_.getitem(topic,0)">
    <dtml-call expr="manage_addFile(id='', file=file, title=short_title)">
    <dtml-call expr="_.getitem(file.filename,0).manage_addProperty('author', author, 'string')">
</dtml-with>