I'm using an html form to upload files to a windows 2k server using
Active Server pages.

The server is in the DMZ and all works fine locally and from the DMZ.
From the Private side using IE or Netscape, the upload only works
occasionally, but with Opera, the upload works perfectly every time
(seems to rule out coding errors / server config).

I've got the enctype of the form set to "MultiPart/Form-Data", as
required by the upload component, which is "Dundas Upload 2".

Access to other web serves in the DMZ are fine though they don't have

any file uploading.

Any idears?