I'm getting "Operation not permitted" in the mini-dinstall.log everytime a new debian package has been uploaded on the custom debian repository using dput. The deb file is installed successfuly but the changes file remains in the incoming folder. I can not use a post-install script when the changes file can not be processed. How can I fix this problem?

Traceback (most recent call last):
  File "/usr/bin/mini-dinstall", line 780, in install
    retval = self._install_run_scripts(changefilename, changefile)
  File "/usr/bin/mini-dinstall", line 826, in _install_run_scripts
    do_chmod(changefilename, 0600)
  File "/usr/bin/mini-dinstall", line 193, in do_chmod
    do_and_log('Changing mode of "%s" to %o' % (name, mode), os.chmod, name, mode)
  File "/usr/bin/mini-dinstall", line 176, in do_and_log
   function(*args)
OSError: [Errno 1] Operation not permitted: '/srv/debian-repository/mini-dinstall/incoming/debian-repository_1.3_amd64.changes'

The mini-dinstall permissions:

ls -lad incoming/
drwxrws--- 2 mini-dinstall debian-repository-uploader 4096 Jun  6 11:45 incoming/

ls -la incoming/debian-repository_1.3_amd64.changes
-rw-rw---- 1 uploader-user debian-repository-uploader 1322 Jun  6 11:43 incoming/debian-repository_1.3_amd64.changes

groups uploader-user
uploader-user : uploader-user adm users debian-repository debian-repository-uploader puppet-client-updater

groups mini-dinstall
mini-dinstall : mini-dinstall debian-repository-uploader

Cheers and thanks V.