Neb. Rev. Stat. § 25-516.01

(1) The voluntary appearance of the party is equivalent to service. (2) A defense of lack of personal jurisdiction, insufficiency of process, or insufficiency of service of process may be asserted only under the procedure provided in the pleading rules adopted by the Supreme Court. If any of those defenses are asserted either by motion or in a responsive pleading and the court overrules the defense, an objection that the court erred in its ruling will be waived and not preserved for appellate review if the party asserting the defense either (a) thereafter files a demand for affirmative relief by way of counterclaim, cross-claim, or third-party claim or (b) fails to dismiss a demand for such affirmative relief that was previously filed. If any of those defenses are asserted either by motion or in a responsive pleading and the court overrules the defense, an objection that the court erred in its ruling on any issue, except an objection to the court's ruling on personal jurisdiction, will be waived and not preserved for appellate review if the party asserting the defense thereafter participates in proceedings on any issue other than those defenses. (3) The filing of a suggestion of bankruptcy is not an appearance and does not waive the defense of lack of personal jurisdiction, insufficiency of process, or insufficiency of service of process.