en protected/config/main.php habilitar el urlManager
'urlManager'=>array(
'urlFormat'=>'path',
'rules'=>array(
'<controller:\w+>/<id:\d+>'=>'<controller>/view',
'<controller:\w+>/<action:\w+>/<id:\d+>'=>'<controller>/<action>',
'<controller:\w+>/<action:\w+>'=>'<controller>/<action>',
),
'showScriptName'=>false,
),
2)
en la raiz de la aplicación el archivo .htaccess debe ser asi
RewriteEngine on
# if a directory or a file exists, use it directly
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond $1 !^(index\.php)
# otherwise forward it to index.php
RewriteRule ^(.+)$ index.php?$1 [PT,L,QSA]