diff --git a/config/filter.d/proftpd.conf b/config/filter.d/proftpd.conf
index ac714cc19b..4bc0ba0183 100644
--- a/config/filter.d/proftpd.conf
+++ b/config/filter.d/proftpd.conf
@@ -2,6 +2,9 @@
 #
 # Set "UseReverseDNS off" in proftpd.conf to avoid the need for DNS.
 # See: http://www.proftpd.org/docs/howto/DNS.html
+# When the default locale for your system is not en_US.UTF-8
+# on Debian-based systems be sure to add this to /etc/default/proftpd
+# export LC_TIME="en_US.UTF-8"
 
 [INCLUDES]