My understanding is that the rank of starszy chorąży sztabowy is the senior of four current WO ranks in the Polish Army as listed on the Polish Ministry of Defence Website:
http://www.wp.mil.pl/strona.php?idstrona=139&idn=2_13_2
The insignia is the same pattern as starszy chorazy but with four stars. It should be included in the current insignia for the Polish Army and Air Force on this site.
The official English Translations of the Polish Warrant Officer ranks should be (from junior to senior)
Warrant Officer 4th Class - Mlodszy Chorąży
Warrant Officer 3rd Class - Chorąży
Warrant Officer 2nd Class - Starszy Chorąży
Warrant Officer 1st Class - Starszy Chorąży Sztabowy
I believe the WO in the links below is the senior WO in the Polish Army:
http://www.army.mil.pl/strona_en/kaleidoscope/wiw/piwonski.htm
http://www.army.mil.pl/strona_pl/kalejdoskop/kto/sylwetki/piwonski.htm
