diff --git a/core/nginx/conf/nginx.conf b/core/nginx/conf/nginx.conf
index 44b6b7ee..80ebdaee 100644
--- a/core/nginx/conf/nginx.conf
+++ b/core/nginx/conf/nginx.conf
@@ -277,6 +277,7 @@ mail {
     server_name {{ HOSTNAMES.split(",")[0] }};
     auth_http http://127.0.0.1:8000/auth/email;
     proxy_pass_error_message on;
+    resolver {{ RESOLVER }} valid=30s;
     error_log /dev/stderr info;
 
     {% if TLS and not TLS_ERROR %}
diff --git a/towncrier/newsfragments/2368.bugfix b/towncrier/newsfragments/2368.bugfix
new file mode 100644
index 00000000..54c29c48
--- /dev/null
+++ b/towncrier/newsfragments/2368.bugfix
@@ -0,0 +1,3 @@
+Re-enable the built-in nginx resolver for traffic going through the mail plugin.
+This is required for passing rDNS/ptr information to postfix.
+Without this rspamd will flag all messages with DHFILTER_HOSTNAME_UNKNOWN due to the missing rDNS/ptr info.
\ No newline at end of file