It’s a notice, not even a warning and not a bug at all. In order to solve this simply go to /etc/proftpd/modules.conf and comment the line that says LoadModule mod_tls_memcache.c by putting the # in front of it, then restart your proftpd by typing /etc/init.d/proftpd restart and your "bug" will disappear.
This merely means that your proftpd was compiled without memcache support. Let me repeat that it’s just a notice as it says, not even a warning, and it’s definitely not a bug at all. It will work perfectly fine with the notice always present on proftpd restarts. However, if you prefer cleaner solutions you may have to consider re-compiling your proftpd with –enable-memcache configure option and your "bug" will also disappear. Good Luck! Regards, Dennis.
