diff --git a/include/polarssl/config.h b/include/polarssl/config.h
index 10b4fb1..3a18f8a 100644
--- a/include/polarssl/config.h
+++ b/include/polarssl/config.h
@@ -1017,6 +1017,7 @@
 // SSL options
 //
 #define SSL_MAX_CONTENT_LEN             16384 /**< Size of the input / output buffer */
+#define SSL_MIN_DHM_BYTES                 128 /**< Min size of the Diffie-Hellman prime */
 
 // X509 options
 //