is very similar to mine, and it was addressed with the less-than-helpful
I'm not 100% sure but I believe these are not always strictly adhered to if you are using HTML format (or replying to an HTML format message) instead of plain text.
Currently, when I reply, outlook prefixes the original with a vertical bar (it even shows a little picture in the options pane). I would like > signs because they're editable. Perhaps it would be sufficient to just be able to break the vertical bar so I can type between lines of the original.
I'm using Outlook 2007 (12.0.6607.1000), Windows XP.