Wis. Stat. § 893.47: Actions against parties jointly liable.

In actions commenced against 2 or more joint contractors or joint personal representatives of any contractors, if it shall appear, on the trial or otherwise, that the plaintiff is barred by this chapter as to one or more of the defendants but is entitled to recover against any other or others of them by virtue of a new acknowledgment or promise or otherwise, judgment shall be given for the plaintiff as to any of the defendants against whom the plaintiff is entitled to recover and for the other defendant or defendants against the plaintiff.