mod_facl
The mod_facl module adds support to ProFTPD for POSIX ACLs. For more information on what POSIX ACLs are and how they work, see "POSIX ACLs on Linux":
http://www.suse.de/~agruen/acl/linux-acls/online/
Installation instructions for mod_facl can be found here. Note that the configure script will automatically determine whether the system supports POSIX ACLs, but it will not automatically make use of that support unless the --enable-facl option is used. In addition, to have ProFTPD fully honor POSIX ACLs on files, you will also need this mod_facl module.
configure
--enable-facl
The most current version of mod_facl can be found in the ProFTPD source distribution:
http://www.proftpd.org/
The FACLEngine directive enables or disables the module's runtime checking of POSIX ACLs. Use this directive to disable the module.
FACLEngine
proftpd
$ ./configure --enable-facl --with-modules=mod_facl ...
Logging The mod_facl module supports trace logging, via the module-specific log channels:
proftpd.conf
TraceLog /path/to/ftpd/trace.log Trace facl:20