warning: chmod() [function.chmod]: Operation not permitted in /sites/all/mediafront/players/osmplayer/player/OSMPlayer.php

   	  // Now make sure the directory has the right permissions.
   	  chmod( $css_dir, 0775 );

When I change the permissions of the css directory to 755 I still get the error message ;(

This should be the best /sites/default/files/mediafront/css or so ;)

I called my provider and asked for this. They said that chmod is enabled cause it's Linux :D

I will test the chmod function with a single php script. Hold on.

Yannick

In my case chmod works only in cgi modus ;)