strange upload and db-insert problem with explorer5.5

dear community, i've got a script which handles the correct upload of certain documents. the way: 1)select the document, then upload through form with method post -> target same document 2)do the checking stuff with the document, if ok call the same script again for displaying the property-page -> form-target same document 3) if everything went well, document-properties are inserted in the db in two tables, then script displays js-redirect to do more stuff with the doc. the problem here is, that although no browser goes wrong, except explorer 5.5 (sp2). using this version, the document's properties are inserted twice, both relating to the same physical doc but with different ids. did anyone ever had same effects or even the remedy for this particular problem? (remedy "get rid of stinkin' ms-junk" won't help, since customer is tied to this trash ;) thanks serge