MIGRATED TO http://wavelet.asia/customer-portal/2011/02/28/contra-supplier-credit-memo/

• Supplier > Credit Memo > Contra
• Enter a Credit Memo PKID and click 'Submit'.
• Enter any amount under Debit or Credit side to contra the credit memo, then click 'Contra'.
  
• Click 'Auto Settle' to make payment to the supplier.

• For more detailed information on the Credit Memo Contra, please refer Contra Customer Credit Memo.