Mozilla just added them this Winter. In related news:

Using ‘man-in-the-middle’ to intercept TLS or SSL is essentially an attack against the underlying Diffie-Hellman cryptographic key agreement protocol [. . . ] To use our product in this scenario, [government] users have the ability to import a copy of any legitimate key they obtain (potentially by court order) or they can generate ‘look-alike’ keys designed to give the subject a false sense of confidence in its authenticity.”