Fatal error: Class 'Abc' not found. A problem about Yii class load.

I have a problem like the problem described in http://www.yiiframework.com/forum/index.php?/topic/14969-solved-fatal-error-class-cerrorevent/ thread.

The application works fine in my development machine(gentoo linux/apache/PHP). But it does not work when I deployed it to my server(freeBSD/apache/PHP). The yii throws a fata error page it says that

Fatal error: Class 'Abc' not found in xxx.file line xxx. 

Indeed the class file Abc.php exists in protected/components/ and the Abc class extends CComponent.

I had tried to solve it according to tread 14969. But it did not work for me. I had tried to require Abc class directly in my Controller class and it also did not work.

It makes me crazy. Please help me.

Have you tested your server with Yii Requirement Checker? Are there a failed result? Take a look in this post about Yii Requirement Checker.

Only PDO PostgreSQL, APC and Memcache do not pass the check. And I do not use these extensions in the project.

It might be a silly question, but just for double checking. What about the case-sensitive issue of file names? Your ftp client could have modified it.

Maybe. I will rewrite the Abc class today.