Deferred Payment Accounting in Payables

I did a setup for deferred payment in accounts payable. All the setups were properly done but whenever i raise a deferred payment transaction and run the complete Multiperiod Accounting Program, the accounting entries are wrong.

For example:

The company pays for services in advance of $12,000.00 and expects to amortize over a period of 12 months (Jan-Dec).

Expected entries

1. Dr Prepayment account $12,000.00

    Cr Vendor/Supplier account $12,000.

Jan Amortization

2. Dr Expense account $1,000.00 Item Expense

    Cr Prepayment account $1,000.00 Expense

Actual entries

Jan Amortization

2. Dr Expense account $1,000.00 .  Item Expense

    Cr Expense account $1,000.00    Expense

The amortization entries is posted into the same account nominated in the distribution line for the transaction. I have done the mapping set and updated the input account combinations.