diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index 40f1673..3f93469 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -137,7 +137,16 @@
 #define SSL_LEGACY_ALLOW_RENEGOTIATION  1
 #define SSL_LEGACY_BREAK_HANDSHAKE      2
 
-#define SSL_MAX_CONTENT_LEN         16384
+/*
+ * Size of the input / output buffer.
+ * Note: the RFC defines the default size of SSL / TLS messages. If you
+ * change the value here, other clients / servers may not be able to
+ * communicate with you anymore. Only change this value if you control
+ * both sides of the connection and have it reduced at both sides!
+ */
+#if !defined(POLARSSL_CONFIG_OPTIONS)
+#define SSL_MAX_CONTENT_LEN         16384   /**< Size of the input / output buffer */
+#endif /* !POLARSSL_CONFIG_OPTIONS */
 
 /*
  * Allow an extra 512 bytes for the record header