diff --git a/scripts/config.pl b/scripts/config.pl
index d8d6a20..7108f50 100755
--- a/scripts/config.pl
+++ b/scripts/config.pl
@@ -31,7 +31,7 @@
 # for our eyes only:
 # $0 [-f <file>] full|realfull
 
-# Things that shouldn't be enabled with "full".
+# The following options are disabled instead of enabled with "full".
 # Notes:
 # - MBEDTLS_X509_ALLOW_EXTENSIONS_NON_V3 and
 #   MBEDTLS_X509_ALLOW_UNSUPPORTED_CRITICAL_EXTENSION could be enabled if the
@@ -47,6 +47,7 @@
 MBEDTLS_NO_PLATFORM_ENTROPY
 MBEDTLS_REMOVE_ARC4_CIPHERSUITES
 MBEDTLS_SSL_HW_RECORD_ACCEL
+MBEDTLS_RSA_NO_CRT
 MBEDTLS_X509_ALLOW_EXTENSIONS_NON_V3
 MBEDTLS_X509_ALLOW_UNSUPPORTED_CRITICAL_EXTENSION
 MBEDTLS_ZLIB_SUPPORT