diff --git a/src/radius/radius.h b/src/radius/radius.h
index e22868817..fb8148180 100644
--- a/src/radius/radius.h
+++ b/src/radius/radius.h
@@ -225,8 +225,9 @@ struct radius_msg;
 /* Default size to be allocated for attribute array */
 #define RADIUS_DEFAULT_ATTR_COUNT 16
 
-/* Maximum message length for incoming RADIUS messages */
-#define RADIUS_MAX_MSG_LEN 3000
+/* Maximum message length for incoming RADIUS messages, as stated in RFC 2865
+ * Section 3 ("Packet Format").*/
+#define RADIUS_MAX_MSG_LEN 4096
 
 /* MAC address ASCII format for IEEE 802.1X use
  * (draft-congdon-radius-8021x-20.txt) */