Appendix A. Changes from RFC 2388

The handling of non-ASCII field names has changed -- the method described in RFC 2047 is no longer recommended; instead, it is suggested that senders send UTF-8 field names directly and that file names be sent directly in the form-charset.

The handling of multiple files submitted as the result of a single form field (e.g., HTML's element) results in each file having its own top-level part with the same name parameter; the method of using a nested "multipart/mixed" from [RFC2388] is no longer recommended for creators and is not required for receivers as there are no known implementations of senders.

The _charset_ convention and use of an explicit "form-data" charset is documented; also, "boundary" is now a required parameter in Content-Type.

The relationship of the ordering of fields within a form and the ordering of returned values within multipart/form-data was not defined before, nor was the handling of the case where a form has multiple fields with the same name.

Various editorial changes were made; they include removing the obsolete discussion of alternatives from the appendix, updating the references, and moving the outline of form processing into the introduction.