Source
--- conf/postfix-script.orig 2014-06-28 00:05:15.000000000 +1000
+++ conf/postfix-script 2015-02-12 15:38:30.000000000 +1100
@@ -288,7 +288,7 @@
# Check Postfix mail_owner-owned directory tree owner.
- find `ls -d $queue_directory/* | \
+ find `/bin/ls -d $queue_directory/* | \
egrep '/(saved|incoming|active|defer|deferred|bounce|hold|trace|corrupt|public|private|flush)$'` \
! \( -type p -o -type s \) ! -user $mail_owner \
-exec $WARN not owned by $mail_owner: {} \;