Calendar class problem

Hi everyone,

Im working with codeigniter for a while and can fix most problems myself. Now I stubled on a problem where I am not sure what the problem really is. I am trying to load the calendar class to generate a calendar. I auto-loaded the class, loaded in the controller's construction method, and tried to load it in the controllers method where I use it. Nothing seems to work because I get this error everytime:

Call to undefined method Calendar::generate()

When I check if the calendar class is loaded it returns a false... I have no idea what the problem is. I did not alter any codeigniter system functions and the class is in the normal directory.

Did anyone had this problem before or understands whats going on here?