diff --git a/platform/sky/contiki-conf.h b/platform/sky/contiki-conf.h
index 1ebe5331f..8eeda6a22 100644
--- a/platform/sky/contiki-conf.h
+++ b/platform/sky/contiki-conf.h
@@ -1,5 +1,5 @@
 /* -*- C -*- */
-/* @(#)$Id: contiki-conf.h,v 1.90 2010/12/16 22:51:22 adamdunkels Exp $ */
+/* @(#)$Id: contiki-conf.h,v 1.91 2011/01/09 21:04:14 adamdunkels Exp $ */
 
 #ifndef CONTIKI_CONF_H
 #define CONTIKI_CONF_H
@@ -50,11 +50,6 @@
 
 /* Network setup for non-IPv6 (rime). */
 
-#define TIMESYNCH_CONF_ENABLED           1
-#if TIMESYNCH_CONF_ENABLED
-#define CC2420_CONF_SFD_TIMESTAMPS       1
-#endif /* TIMESYNCH_CONF_ENABLED */
-
 #define NETSTACK_CONF_NETWORK rime_driver
 
 #define COLLECT_CONF_ANNOUNCEMENTS       1
@@ -74,6 +69,16 @@
 #define QUEUEBUF_CONF_NUM                16
 #endif /* QUEUEBUF_CONF_NUM */
 
+#ifndef TIMESYNCH_CONF_ENABLED
+#define TIMESYNCH_CONF_ENABLED           0
+#endif /* TIMESYNCH_CONF_ENABLED */
+
+#if TIMESYNCH_CONF_ENABLED
+/* CC2420 SDF timestamps must be on if timesynch is enabled. */
+#undef CC2420_CONF_SFD_TIMESTAMPS
+#define CC2420_CONF_SFD_TIMESTAMPS       1
+#endif /* TIMESYNCH_CONF_ENABLED */
+
 #endif /* WITH_UIP6 */
 
 #define PACKETBUF_CONF_ATTRS_INLINE 1