在php.ini添加扩展，重启后还是无法加载新扩展

[root@aaaaa no-debug-non-zts-20131226]# ll
total 3080
-rwxr-xr-x 1 root root 855986 Jan 22 21:55 imagick.so
-rwxr-xr-x 1 root root 1002668 Jan 22 21:55 ioncube_loader_lin_5.6.so
-rwxr-xr-x 1 root root 520873 Jan 22 21:49 opcache.so
-rwxr-xr-x 1 root root 92642 Jul 16 11:31 protobuf.so
-rwxr-xr-x 1 root root 673666 Jan 22 21:57 redis.so
php.ini文件:
extension_dir = "/usr/local/php/lib/php/extensions/no-debug-non-zts-20131226"
extension = "redis.so"
extenstion = "protobuf.so"
;extension = "imagick.so"