IAX2 plaintext authentication

Hi,

The plaintext authentication method on IAX2 is still supported by asterisk?
I’ve setup an IAX2 extension with this method, but when I see the information element on wireshark it say “Reserved”.

From the client I don’t found a valid information element for response a plaintext authentication. Only for MD5 or RSA.

(bump)
So… the iax2 plaintext authentication is deprecated? There is no Information Element for reply this method?