diff --git a/Propellor/Property/Hostname.hs b/Propellor/Property/Hostname.hs
index 03613ac..59aade4 100644
--- a/Propellor/Property/Hostname.hs
+++ b/Propellor/Property/Hostname.hs
@@ -4,11 +4,12 @@ import Propellor
 import qualified Propellor.Property.File as File
 
 -- | Ensures that the hostname is set to the HostAttr value.
--- Configures both /etc/hostname and the current hostname.
+-- Configures /etc/hostname and the current hostname.
 --
--- When the hostname is a FQDN, also configures /etc/hosts,
--- with an entry for 127.0.1.1, which is standard at least on Debian
--- to set the FDQN (127.0.0.1 is localhost).
+-- When the hostname is a FQDN, also configures /etc/mailname
+-- with the domain part.
+-- A FQDN also configures /etc/hosts, with an entry for 127.0.1.1, which is
+-- standard at least on Debian to set the FDQN (127.0.0.1 is localhost).
 sane :: Property
 sane = Property ("sane hostname") (ensureProperty . setTo =<< getHostName)
 
@@ -25,6 +26,9 @@ setTo hn = combineProperties desc go
 			then Nothing 
 			else Just $ File.fileProperty desc
 				addhostline "/etc/hosts"
+		, if null domain
+			then Nothing
+			else Just $ "/etc/mailname" `File.hasContent` [domain]
 		]
 	
 	hostip = "127.0.1.1"