class.upload.php is a powerful and mature PHP class to manage uploaded files, and manipulate images in many ways. The script is available under a GPL license.
more info about the class
$this->mime_fileinfo = false; $this->mime_file = false; $this->mime_magic = false; $this->mime_getimagesize = true;
issue solved seems like mime_content_type was causing the trouble
fix = disabled mime detection methods in upload class init() function
cheers :)