1.5: /?tegory%/%postname%.php dont work

When I have /%category%/%postname%.php, It doesnt work. When I have /%category%/%postname%, It doesnt work. WHen I have, /%year%/%monthnum%/%day%/%postname%/ , It works. Whats wrong?…I want /%category%/%postname%.php but It doesnt work and %category%/%postname% doesnt even work. And the slash at the end doesnt matter.