diff --git a/core/net/rime/queuebuf.c b/core/net/rime/queuebuf.c
index a4fc48901..223abe5b3 100644
--- a/core/net/rime/queuebuf.c
+++ b/core/net/rime/queuebuf.c
@@ -28,7 +28,7 @@
  *
  * This file is part of the Contiki operating system.
  *
- * $Id: queuebuf.c,v 1.5 2007/03/23 10:46:35 adamdunkels Exp $
+ * $Id: queuebuf.c,v 1.6 2007/03/29 22:22:20 adamdunkels Exp $
  */
 
 /**
@@ -42,8 +42,17 @@
 
 #include <string.h> /* for memcpy() */
 
+#ifdef QUEUEBUF_CONF_NUM
+#define QUEUEBUF_NUM QUEUEBUF_CONF_NUM
+#else
 #define QUEUEBUF_NUM 2
+#endif
+
+#ifdef QUEUEBUF_CONF_REF_NUM
+#define QUEUEBUF_REF_NUM QUEUEBUF_CONF_REF_NUM
+#else
 #define QUEUEBUF_REF_NUM 2
+#endif
 
 struct queuebuf {
   u16_t len;
diff --git a/core/net/rime/rimebuf.h b/core/net/rime/rimebuf.h
index 59b16a1e2..6f8049446 100644
--- a/core/net/rime/rimebuf.h
+++ b/core/net/rime/rimebuf.h
@@ -28,7 +28,7 @@
  *
  * This file is part of the Contiki operating system.
  *
- * $Id: rimebuf.h,v 1.6 2007/03/24 16:42:43 adamdunkels Exp $
+ * $Id: rimebuf.h,v 1.7 2007/03/29 22:22:20 adamdunkels Exp $
  */
 
 /**
@@ -46,12 +46,20 @@
 /**
  * \brief      The size of the rimebuf, in bytes
  */
+#ifdef RIMEBUF_CONF_SIZE
+#define RIMEBUF_SIZE RIMEBUF_CONF_SIZE
+#else
 #define RIMEBUF_SIZE 128
+#endif
 
 /**
  * \brief      The size of the rimebuf header, in bytes
  */
+#ifdef RIMEBUF_CONF_HDR_SIZE
+#define RIMEBUF_HDR_SIZE RIMEBUF_CONF_HDR_SIZE
+#else
 #define RIMEBUF_HDR_SIZE 32
+#endif
 
 /**
  * \brief      Clear and reset the rimebuf