In Zend Framework 1.12, what's the case sensitive rules for Controller,Action

In Zend Framework 1.12, what's the case sensitive rules for Controller,Action

I'm using the Zend Framework 1.12 in a project.
Something is so weird. I haven't use the Module. Just the Controller and
Action.
My Controller file name is MyCCController.php, 'CC' is upper case.
My action in this controller file is MyAAAction ,'AA' is upper case.
I tried the url http://localhost:8003/Mycc/myAA. It shows the error-'Page
not found'. I googled and see some one said action name must be lower
case. So I change the 'MyAAAction' to 'myaaAction'. And the .phtml file is
sitll 'views\scripts\MyCC\MyAA.phtml'. It doesn't care about the uppercase
or lowercase.
Then I visited the url http://localhost:8003/MyCC/myaa, It still shows
'Page not found'.
I changed the url http://localhost:8003/Mycc/myaa, 'CC' became 'cc'.Then
It's OK.
So my question is that is there any article elaborating the MVC URL case
sensitive rules?
Or who can give me the rule about the name of controller,action,*.phtml
file or something relative.
And if I need the action Name as camelCase, how to realize it?