Portuguese accents on gnuplot

set encoding iso_8859_1
set ylabel “Requisi{/E \347}{/E \365}es/s/W”

Character list:
http://www.dcf.ds.mpg.de/fileadmin/mitarbeiter/Matthias_Schroeter/various/gnuplot/ps_guide.pdf

Other information:
http://wiki.ipb.ac.rs/index.php/Gnuplot