diff --git a/ChangeLog b/ChangeLog
index f011fdef5..7c2b55e3b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2011-11-11  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	* grub-core/kern/ieee1275/openfw.c (grub_ieee1275_parse_args):
+	Issue error rather than printf on unknown arguments.
+
 2011-11-11  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* grub-core/kern/ieee1275/ieee1275.c (grub_ieee1275_set_property):
diff --git a/grub-core/kern/ieee1275/openfw.c b/grub-core/kern/ieee1275/openfw.c
index 57252d96b..3568ffe64 100644
--- a/grub-core/kern/ieee1275/openfw.c
+++ b/grub-core/kern/ieee1275/openfw.c
@@ -403,7 +403,8 @@ grub_ieee1275_parse_args (const char *path, enum grub_ieee1275_parse_type ptype)
       break;
     default:
     unknown:
-      grub_printf ("Unsupported type %s for device %s\n", type, device);
+      grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
+		  "unsupported type %s for device %s", type, device);
     }
 
 fail: