diff --git a/cmdeploy/src/cmdeploy/postfix/main.cf.j2 b/cmdeploy/src/cmdeploy/postfix/main.cf.j2
index ab881b9a..856996bb 100644
--- a/cmdeploy/src/cmdeploy/postfix/main.cf.j2
+++ b/cmdeploy/src/cmdeploy/postfix/main.cf.j2
@@ -99,4 +99,6 @@ smtpd_peername_lookup = no
 # when specifying a custom next-hop,
 # so instead this is handled in filtermail.
 # We use LMTP instead SMTP so we can communicate per-recipient errors back to postfix.
-#default_transport = lmtp-filtermail:inet:[127.0.0.1]:{{ config.filtermail_lmtp_port_transport }}
+default_transport = lmtp-filtermail:inet:[127.0.0.1]:{{ config.filtermail_lmtp_port_transport }}
+lmtp-filtermail_initial_destination_concurrency=10000
+lmtp-filtermail_destination_concurrency_limit=10000
diff --git a/cmdeploy/src/cmdeploy/postfix/master.cf.j2 b/cmdeploy/src/cmdeploy/postfix/master.cf.j2
index 34081b28..0d6e3f79 100644
--- a/cmdeploy/src/cmdeploy/postfix/master.cf.j2
+++ b/cmdeploy/src/cmdeploy/postfix/master.cf.j2
@@ -101,7 +101,7 @@ filter    unix -        n       n       -       -       lmtp
 authclean unix  n       -       -       -       0       cleanup
   -o header_checks=regexp:/etc/postfix/submission_header_cleanup
 
-lmtp-filtermail unix  -       -       y       -       -       lmtp
+lmtp-filtermail unix  -       -       y       -       10000       lmtp
   -o syslog_name=postfix/lmtp-filtermail
   -o lmtp_header_checks=
   -o lmtp_tls_security_level=none