What is the test for a motion to vacate a judgment against a defendant who has been defrauded by his attorney?

"The court may grant relief under its inherent equity power if, because of the fraud of his opponent, the aggrieved party was prevented from presenting his claim or defense to the court. [Citations.] 'Two essential conditions are found in a classic case in equity which seeks to set aside a judgment: first, the judgment is one entered against a party by default under circumstances which prevented him from presenting his case; second, these circumstances result from extrinsic fraud practiced by the other party or his attorney.' [Citation.] The vital question is 'whether the successful party has by inequitable conduct, either direct or insidious in nature, lulled the other party into a state of false security, thus causing the latter to refrain from appearing in court or asserting legal rights.' [Citation.] A party who seeks to have his default vacated under the court's equity power must make a [67 Cal.App.4th 315] stronger showing than is necessary to obtain relief under section 473. [Citation.] '[D]uring the period when relief under section 473 is available, there is a strong public policy in favor of granting relief and allowing the requesting party his or her day in court. Beyond this period there is a strong public policy in favor of the finality of judgments and only in exceptional circumstances should relief be granted.' " (Aheroni v. Maxwell, supra, 205 Cal.App.3d at pp. 291-292, 252 Cal.Rptr. 369.)