diff --git a/WINGs/userdefaults.c b/WINGs/userdefaults.c
index cb2cc051..3553b361 100644
--- a/WINGs/userdefaults.c
+++ b/WINGs/userdefaults.c
@@ -102,11 +102,7 @@ char *wglobaldefaultspathfordomain(const char *domain)
 }
 
 static void
-#ifdef HAVE_ATEXIT
 saveDefaultsChanges(void)
-#else
-saveDefaultsChanges(int foo, void *bar)
-#endif
 {
 	/* save the user defaults databases */
 	synchronizeUserDefaults(NULL);
@@ -118,11 +114,7 @@ static void registerSaveOnExit(void)
 	static Bool registeredSaveOnExit = False;
 
 	if (!registeredSaveOnExit) {
-#ifdef HAVE_ATEXIT
 		atexit(saveDefaultsChanges);
-#else
-		on_exit(saveDefaultsChanges, (void *)NULL);
-#endif
 		registeredSaveOnExit = True;
 	}
 }
diff --git a/configure.ac b/configure.ac
index 9afae793..0363c4a0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -163,7 +163,7 @@ dnl not used anywhere
 AC_FUNC_MEMCMP
 AC_FUNC_VPRINTF
 AC_CHECK_FUNCS(gethostname select poll strcasecmp strncasecmp \
-	       setsid atexit mallinfo mkstemp sysconf)
+	       setsid mallinfo mkstemp sysconf)
 
 dnl Check for strlcat/strlcpy
 dnl =========================