By default, the installed package refused to start, because of missing files. So I had to do the following to resolve the missing links:
First, create a symbolic link to the already existing file:
ln -s ‘/usr/sbin/proftpd’ ‘/usr/sbin/in.ftpd’
Second, let’s tell inetd where to look for the service program, edit yours as follows (the default location is at /etc/inetd.conf):
ftp stream tcp nowait root /usr/sbin/tcpd /usr/sbin/proftpd
After that, let’s restart the service altogether:
service proftpd restart
There you go! 🙂
Source available here.