diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index 24e60f7..5b4e36f 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -117,7 +117,8 @@
 #define SSL_MINOR_VERSION_2             2   /*!< TLS v1.1 */
 #define SSL_MINOR_VERSION_3             3   /*!< TLS v1.2 */
 
-/* RFC 6066 section 4 */
+/* RFC 6066 section 4, see also mfl_code_to_length in ssl_tls.c
+ * NONE must be zero so that memset()ing session to zero works */
 #define SSL_MAX_FRAG_LEN_NONE           0   /*!< don't use this extension   */
 #define SSL_MAX_FRAG_LEN_512            1   /*!< MaxFragmentLength 2^9      */
 #define SSL_MAX_FRAG_LEN_1024           2   /*!< MaxFragmentLength 2^10     */
@@ -509,7 +510,6 @@
 
     /* Maximum fragment length extension (RFC 6066 section 4) */
     unsigned char mfl_code;     /*!< numerical code for MaxFragmentLength   */
-    uint16_t max_frag_len;      /*!< value of MaxFragmentLength             */
 
     /*
      * PKI layer