diff --git a/install/tpl/mailfilter.master b/install/tpl/mailfilter.master
index 54d0b859658530d7f4e405b47133c268a09f186f..8588b14876800abf75446dff4181516bcd7c0706 100644
--- a/install/tpl/mailfilter.master
+++ b/install/tpl/mailfilter.master
@@ -5,8 +5,8 @@
 LOGNAME=tolower("$LOGNAME")
 EXTENSION="$1"
 RECIPIENT=tolower("$2")
-USER="$3"
-HOST="$4"
+USER=tolower("$3")
+HOST=tolower("$4")
 SENDER="$5"
 DEFAULT="{dist_postfix_vmail_mailbox_base}/$HOST/$USER/."