I've got a document style sheet that puts the paragraphsign ¶ in front of the paragraph number. It shows up fine in the document, both at the start of the paragraph and in the table of contents, but in the PDF outlines, it shows up as ű.
If I then run the command:
pdftk inputfile.pdf dump_data_utf8 | sed -r -e 's,ű,¶,g' | pdftk inputfile.pdf update_info_utf8 - output outputfile.pdf
... the resulting PDF has the paragraphsign in the outlines the way it's supposed to. I guess if I actually used that thing that looks like a u with a double quote above it in the text of the document in any section or paragraph headings, there would be paragraph signs instead of that letter there, which would not be correct.