The provisions of 11 U.S.C. ยง 506(d) avoid the lien of FNRS because it does not hold an allowed secured claim, as was determined by the order sustaining the trustee's contest of claim. In re Smoot, 134 B.R. 960, 963 (Bankr.N.D.Ala. 1991). As the Thomas court acknowledged, "an unchallenged lien survives the discharge of the debtor in bankruptcy".
Res judicata, which is the basis for the binding effect of a confirmed plan, see Stoll v. Gottlieb, 305 U.S. 165, 59 S.Ct. 134, 83 L.Ed. 104 (1938); Bowen v. United States (In re Bowen), 174 B.R. 840 (Bankr.S.D.Ga. 1994), binds the creditor to the terms of the plan and precludes relitigation of issues which either were previously decided or could have been previously decided. Id. A non-filing secured creditor who is not provided for under a plan is nevertheless bound to the terms of a plan in the sense that it is subject to the automatic stay, Smoot v. Southtrust Mobile Services, Inc. (In re Smoot), 134 B.R. 960 (Bankr.N.D.Ala. 1991), and must accept the treatment the debtor affords its claim under the plan for the debtor's discharge of personal liability. Thus, a secured creditor who does not file a proof of claim and is not provided for in a plan is bound to receive nothing under the plan, and may not seek a deficiency from the debtors.