ProFTPD: without system users

install proftpd
edit /etc/proftpd/proftpd.conf:
RequireValidShell off
AuthOrder mod_auth_file.c
AuthUserFile /etc/proftpd/ftpd.passwd
AuthGroupFile /etc/proftpd/ftpd.group
DefaultRoot ~
wget http://www.castaglia.org/proftpd/contrib/ftpasswd
chmod +x ftpasswd
./ftpasswd --passwd --file=/etc/proftpd/ftpd.passwd --name=john --uid=1 --gid=1 --home=/home/ftp --shell=/bin/false
when creating the next user uid increases by 1.
chmod 777 /home/ftp
/etc/init.d/proftpd restart