P's non-priority unsecured debts consist of some $19,000 owed the IRS; $18,000 owed the county for child support payments (he is now current); and $500 owed to a pair of trade creditors. The county debt is nondischargeable. P proposed to divide the debts into two classes, one consisting of the debt to the county and the other of the other debts. County debt would be paid two-thirds, and the second class of unsecured creditors will get nothing. The court refused to confirm the plan under Section 1322(b). The district court affirmed, and P appealed.