I’m setting up proftpd on debian, using openbsd-inetd. One glitch so far:

Dec  8 17:07:34 little-valley-1-140 proftpd[31772]: Fatal: LoadModule: error loading module 'mod_lang.c': Permission denied on line 38 of '/etc/proftpd/modules.conf' 

I commented that out, and now getting this:

Dec 08 17:09:24 little-valley-1-140 proftpd[31821]: warning: unable to determine IP address of 'little-valley-1-140'

Dec 08 17:09:24 little-valley-1-140 proftpd[31821]: error: no valid servers configured

Dec 08 17:09:24 little-valley-1-140 proftpd[31821]: Fatal: error processing configuration file '/etc/proftpd/proftpd.conf'

In the end I ended up running proftpd in standalone mode, and its working fine.

ProFTPd howto