Is a personal injury release valid when the statute of limitations has run?

In Casey v. Proctor, supra, 59 Cal.2d 97, 28 Cal.Rptr. 307, 378 P.2d 579, upon which appellants rely, the court enunciated special rules applicable to releases executed for personal injuries (p. 112, 28 Cal.Rptr. 307, 378 P.2d 579). But the policy of the law applicable in this case is stated therein, at page 111, 28 Cal.Rptr. at page 315, 378 P.2d at page 587: 'On the one hand, the policy of the law is to encourage out-of-court settlements. To further this policy the parties to a dispute should be encouraged to negotiate settlements and to enter into releases. In the absence of unfair conduct on the part of the releasee, the law should extend its protection to the stability of the transaction by holding the parties to the express terms of the release. If later discovered injuries may be asserted, no release would be final and free from attack until the statute of limitations has run.'