diff --git a/src/netif/ppp/polarssl/README b/src/netif/ppp/polarssl/README
index 71f78fa9..ff6e44db 100644
--- a/src/netif/ppp/polarssl/README
+++ b/src/netif/ppp/polarssl/README
@@ -19,13 +19,12 @@ LWIP_INCLUDED_POLARSSL_MD4   ; Use lwIP internal PolarSSL for MD4
 LWIP_INCLUDED_POLARSSL_MD5   ; Use lwIP internal PolarSSL for MD5
 LWIP_INCLUDED_POLARSSL_SHA1  ; Use lwIP internal PolarSSL for SHA1
 LWIP_INCLUDED_POLARSSL_DES   ; Use lwIP internal PolarSSL for DES
+LWIP_INCLUDED_POLARSSL_ARC4  ; Use lwIP internal PolarSSL for ARC4
 
 If set (=1), the default if required by another enabled PPP feature unless
 explicitly set to 0, using included lwIP PolarSSL.
 
-If clear (=0), using external PolarSSL.
-
-Undefined if not needed.
+If clear (=0), not needed or using external PolarSSL.
 
 Beware of the stack requirements which can be a lot larger if you are not
 using our cleaned PolarSSL library.