Cannot get exec in php working help?

Hey guys I am having a problem. Right now I am running my own fedora 8 test server with the latest apache php ispconfig ffmpeg with all libraries and pretty much anything else you could think of that a web server would have like mail.

Anyways thats my system, my problem is I cannot do anything with the command exec(). I am not running in safe mode or anything. I tried moving a link to the program i want to execute into my web folder so that i was sure that its not the URL within my system that is messing it up.

things i have tried is mkdir within my web folder and i tried to exec ffmpeg on a video because what i am trying to do is server side video conversions.
My code for this is.

$cmd = 'ffmpeg -i Tool - VICARIOUS.avi -b 96k -r 18 -s cif -ra 44100 Tool3.flv > test.txt'
$output = exec($cmd, $error);

Now there is nothing in test.txt and there is no tool3 file within the entire filesystem. I also tried this

$output = exec('ffmpeg -i Tool - VICARIOUS.avi -b 96k -r 18 -s cif -ra 44100 Tool3.flv > test.txt', $error);

AND this

exec('ffmpeg -i Tool - VICARIOUS.avi -b 96k -r 18 -s cif -ra 44100 Tool3.flv', $error);

Nothing seems to work.

I also tried using shell_exec but that did not work aswell. If you guys could give me any pointers as to where or what i might check to get this working i would GREATLY appreciate it
Thanks.