/etc/apache2/sites-available/default

  <Directory />
    Options FollowSymLinks
#   AllowOverride None
    AllowOverride ExecCGI
  </Directory>

Illegal override option ExecCGI
 failed!

AllowOverrideは使えないので

  <Directory /home/hoge/www>
    Options +ExecCGI
  </Directory>