Index: terminal/terminal-preferences.c
===================================================================
--- terminal/terminal-preferences.c	(revision 21729)
+++ terminal/terminal-preferences.c	(working copy)
@@ -1351,7 +1351,10 @@
 
   dst = preferences->values + prop_id;
   if (!G_IS_VALUE (dst))
-    g_value_init (dst, pspec->value_type);
+    {
+      g_value_init (dst, pspec->value_type);
+      g_param_value_set_default (pspec, dst);
+    }
 
   if (g_param_values_cmp (pspec, value, dst) != 0)
     {