Fixed in cups-filters upstream, BZR rev. 7455. Thank you very much for the bug report.
The wrong documentation of the input formats of sys5ippprinter was also in the man page of cups-browsed.conf (utils/cups-browsed.conf.5) and in README. I have fixed it there, too.
The fix will appear in cups-filters releases from 1.8.4 on. Till
