I have this message too. My files upload ok (1.5 stable), but when I try to access them I see that moodle has a hyperlink with the wrong path - it points to the main moodle directory and not the moodledata directory (where the files were placed) and has in the path inserted 'file.php/' before the folder.
I guess this is a bug. A fix would be much appreciated as the ability to download files with my courses is essential.
Please please will someone fix this. Thanks. Ray