[url=http://pcgamingwiki.com/wiki/Star_Wars:_Jedi_Knight_%E2%80%93_Jedi_Academy#Widescreen_resolution]http://pcgamingwiki.com/wiki/Star_Wars:_Jedi_Knight_%E2%80%93_Jedi_Academy#Widescreen_resolution[/url]

Open the console with shift + the key under esc
type in these commands seperately:
r_customwidth 1920
r_customheight 1080
r_mode -1
vid_restart