priority strings

Hi,

My code is trying to do:

  gnutls_priority_init(NONE:+VERS-TLS-ALL:+MAC-ALL:+RSA:+AES-128-CBC:+CAMELLIA-256-GCM:+SIGN-ALL:+COMP-NULL)

This used to work, I think with a previous library version.
Under GnuTLS 3.6.3 (on f28) I'm getting:

  "failed at offset 0, "NONE:+VE.." failed: No or insufficient priorities were set".


The manual at https://gnutls.org/manual/html_node/Priority-Strings.html still
says, in Table 6.3 for "NONE":

  "Means nothing is enabled. This disables even protocol versions. It should be followed by the algorithms to be enabled."




What should I now be using?
-- 
Thanks,
  Jeremy