@Override
    public <T> void writeObject(int fieldNumber, T value, Schema<T> innerSchema, boolean repeated) throws IOException
    {

        MsgpackGenerator innerGenerator = new MsgpackGenerator(generator.isNumeric());

        MsgpackGenerator thisGenerator = this.generator;
        Schema<?> thisSchema = this.schema;

        use(innerGenerator, innerSchema);

        innerSchema.writeTo(this, value);

        use(thisGenerator, thisSchema);

        generator.pushValue(this.schema, fieldNumber, innerGenerator.toValue(), repeated);

    }
Before serializing a message/object tied to a schema, this should be called. This also resets the internal state
of this output.
protostuff-msgpack/src/main/java/io/protostuff/MsgpackOutput.java