diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index 7de1577..ff0e9d1 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -564,6 +564,7 @@
 }
 #endif /* POLARSSL_ECP_C */
 
+#if defined(POLARSSL_SSL_MAX_FRAGMENT_LENGTH)
 static int ssl_parse_max_fragment_length_ext( ssl_context *ssl,
                                               const unsigned char *buf,
                                               size_t len )
@@ -578,6 +579,7 @@
 
     return( 0 );
 }
+#endif /* POLARSSL_SSL_MAX_FRAGMENT_LENGTH */
 
 static int ssl_parse_truncated_hmac_ext( ssl_context *ssl,
                                          const unsigned char *buf,
@@ -1174,6 +1176,7 @@
             break;
 #endif /* POLARSSL_ECP_C */
 
+#if defined(POLARSSL_SSL_MAX_FRAGMENT_LENGTH)
         case TLS_EXT_MAX_FRAGMENT_LENGTH:
             SSL_DEBUG_MSG( 3, ( "found max fragment length extension" ) );
 
@@ -1181,6 +1184,7 @@
             if( ret != 0 )
                 return( ret );
             break;
+#endif /* POLARSSL_SSL_MAX_FRAGMENT_LENGTH */
 
         case TLS_EXT_TRUNCATED_HMAC:
             SSL_DEBUG_MSG( 3, ( "found truncated hmac extension" ) );
@@ -1386,6 +1390,7 @@
     *olen = 5 + ssl->verify_data_len * 2;
 }
 
+#if defined(POLARSSL_SSL_MAX_FRAGMENT_LENGTH)
 static void ssl_write_max_fragment_length_ext( ssl_context *ssl,
                                                unsigned char *buf,
                                                size_t *olen )
@@ -1410,6 +1415,7 @@
 
     *olen = 5;
 }
+#endif /* POLARSSL_SSL_MAX_FRAGMENT_LENGTH */
 
 static int ssl_write_server_hello( ssl_context *ssl )
 {
@@ -1551,8 +1557,10 @@
     ssl_write_renegotiation_ext( ssl, p + 2 + ext_len, &olen );
     ext_len += olen;
 
+#if defined(POLARSSL_SSL_MAX_FRAGMENT_LENGTH)
     ssl_write_max_fragment_length_ext( ssl, p + 2 + ext_len, &olen );
     ext_len += olen;
+#endif
 
     ssl_write_truncated_hmac_ext( ssl, p + 2 + ext_len, &olen );
     ext_len += olen;