ken@ubuntu:~$ xmodmap .Xmodmap
xmodmap:  .Xmodmap:2:  bad remove modifier name 'space', not allowed
xmodmap:  .Xmodmap:3:  bad keysym target key symbol 'Space'
xmodmap:  .Xmodmap:4:  bad keysym name 'Space' in keysym list
xmodmap:  .Xmodmap:6:  bad add modifier name 'space', not allowed
xmodmap:  4 errors encountered, aborting.