Chapter 13 debtors moved to disallow creditors' proof of claim, which listed their claim as secured. The court held that chapter 13 debtors do not have 11 U.S.C. § 544 "strong-arm powers," which may only be exercised by chapter 13 trustees. Allowing debtors to exercise such powers, absent a chapter 13 provision that specifically grants them to debtors, as does 11 U.S.C. § 1107(a) in chapter 11 cases, would do violence to the rules of statutory construction.