The summons in such suit shall be served on the Attorney General in the mode prescribed by law for the service of a summons in other cases; and he shall appear for the state. The suit shall be proceeded with as if it were between private persons; but a bill shall not be taken as confessed nor a judgment by default be rendered against the state. The answer of the state to any bill need not be under oath or under the great seal, but may be made by the Attorney General for the state.