diff --git a/cf/m4/proto.m4 b/cf/m4/proto.m4

index 3bc4c77..74e62b5 100644

--- a/cf/m4/proto.m4

+++ b/cf/m4/proto.m4

@@ -1891,6 +1891,8 @@ R<@> < $* @ [127.0.0.1] >

 			$: < ? $&{client_name} > < $1 @ [127.0.0.1] >

 R<@> < $* @ localhost.$m >

 			$: < ? $&{client_name} > < $1 @ localhost.$m >

+R<@> < $* @ localhost.localdomain >

+			$: < ? $&{client_name} > < $1 @ localhost.localdomain >

 ifdef(`_NO_UUCP_', `dnl',

 `R<@> < $* @ localhost.UUCP >

 			$: < ? $&{client_name} > < $1 @ localhost.UUCP >')