400.3-601. (a) The obligation of a party to pay theinstrument is discharged as stated in this Article or by an actor agreement with the party which would discharge an obligationto pay money under a simple contract.
(b) Discharge of the obligation of a party is not effectiveagainst a person acquiring rights of a holder in due course ofthe instrument without notice of the discharge.
(L. 1963 p. 503 ยง 3-601, A.L. 1992 S.B. 448)