diff --git a/data/templates/postfix/postsrsd b/data/templates/postfix/postsrsd
index 56bfd091e..a0451faf6 100644
--- a/data/templates/postfix/postsrsd
+++ b/data/templates/postfix/postsrsd
@@ -12,7 +12,7 @@ SRS_DOMAIN={{ main_domain }}
 # the domain itself. Separate multiple domains by space or comma.
 # We have to put some "dummy" stuff at start and end... see this comment :
 # https://github.com/roehling/postsrsd/issues/64#issuecomment-284003762
-SRS_EXCLUDE_DOMAINS=dummy {{ domain_list }} dummy
+SRS_EXCLUDE_DOMAINS="dummy {{ domain_list }} dummy"
 
 # First separator character after SRS0 or SRS1.
 # Can be one of: -+=