Verify receipt functionality in PS Expense 9.1

We are testing required receipt functionality in PS 9.1 Maintenance pack # 20

Steps:

1. On the Expense BU definition- Minimum receipt required value is 25 USD

2. On the receipt verification rule page - receipt required flag and verify receipts boxes are check marked

3. Created an expense report for 50 USD without any receipt

4 Supervisor is able to approve

5 Prepay auditor is able to approve and status is changed to approved

I was thinking that at some level system will not allow to approve this Expense report.

Please let me know if this functionality is working in 9.1 and how

Thanks!