diff --git a/src/dbusbind.c b/src/dbusbind.c
index d96b735c79a..96f9329a97e 100644
--- a/src/dbusbind.c
+++ b/src/dbusbind.c
@@ -276,7 +276,9 @@ XD_OBJECT_TO_STRING (Lisp_Object object)

 #define XD_DBUS_VALIDATE_BUS_ADDRESS(bus)				\
   do {									\
-    char const *session_bus_address = getenv ("DBUS_SESSION_BUS_ADDRESS"); \
+    Lisp_Object session_bus_address					\
+      = Fgetenv_internal (build_string ("DBUS_SESSION_BUS_ADDRESS"),	\
+			  Qnil);					\
     if (STRINGP (bus))							\
       {									\
 	DBusAddressEntry **entries;					\
@@ -289,9 +291,8 @@ #define XD_DBUS_VALIDATE_BUS_ADDRESS(bus)				\
 	dbus_error_free (&derror);					\
 	dbus_address_entries_free (entries);				\
 	/* Canonicalize session bus address.  */			\
-	if ((session_bus_address != NULL)				\
-	    && (!NILP (Fstring_equal					\
-		       (bus, build_string (session_bus_address)))))	\
+	if ((STRINGP (session_bus_address))				\
+	    && (!NILP (Fstring_equal (bus, session_bus_address))))	\
 	  bus = QCsession;						\
       }									\
 									\
@@ -304,7 +305,7 @@ #define XD_DBUS_VALIDATE_BUS_ADDRESS(bus)				\
 	  XD_SIGNAL2 (build_string ("Wrong bus name"), bus);		\
 	/* We do not want to have an autolaunch for the session bus.  */ \
 	if ((EQ (bus, QCsession) || EQ (bus, QCsession_private))	\
-	    && session_bus_address == NULL)				\
+	    && NILP (session_bus_address))				\
 	  XD_SIGNAL2 (build_string ("No connection to bus"), bus);	\
       }									\
   } while (0)