In the following code of CipherSuite.java:
---------------------------------------------------------
    /*
     * Use this method when there is no lower protocol limit where this
     * suite can be used, and the PRF is P_SHA256. That is, the
     * existing ciphersuites. From RFC 5246:
     *
     * All cipher suites in this document use P_SHA256.
     */
    private static void add(String name, int id, int priority,
            KeyExchange keyExchange, BulkCipher cipher,
            boolean allowed, int obsoleted) {
        // If this is an obsoleted suite, then don't let the TLS 1.2
        // protocol have a valid PRF value.
        PRF prf = P_SHA256;
        if (obsoleted < ProtocolVersion.TLS12.v) {
            prf = P_NONE;
        }

        add(name, id, priority, keyExchange, cipher, allowed, obsoleted,
            ProtocolVersion.LIMIT_MIN_VALUE, prf);
    }
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it is commented that "don't let the TLS 1.2 protocol have a valid PRF value". However, the following code uses P_SHA256 as the PRF if the obsoleted version is TLS12.