Can't create Cache file after install...

This isn't really a problem anymore (I've solved it as far as i'm concerned) - but I'm hoping I can save someone else the hassle. (if they are equally as new to linux as me).
I installed a fresh version of Fedora Core 3 and got running everything needed for PunBB. I installed it, it created the databases and finished everything happily. Got to the "create the config.php" file screen of install and it told me "cache" and "img/avatars" were not writeable & that I should chmod 0777 them if I was struggling. Makes perfect sense.... Except ... it didn't work...

I then tried many many extreme idea's before deciding start taking some @'s of the code it was failing on in the PHP to get the error messages actually being given by PHP. Got these error messages and it was clearly saying it STILL didn't have permissions (by this time everything is owned by the apache user and 777'd). I started to get frustrated till I finally found the little devil.

SELinux is enabled.... simply disable it to allow PHP to write to directories outside of /tmp
(or of course - you could alter some of the settings maybe? I never tried this as the box I'm working on is a development box and won't be used as live).

Problem solved.

Again - probably something someone even slightly more linux trained than a goldfish-on-the-dole could have spotted.... But I'm not that goldfish sadly and it took me a while.