Credit memos are created in the same transaction type as invoice

Hi

In implementaion option in Project we have updated a source for invoiceing say PROJECT INVOICE SOURCE

We have created a transaction type PROJECT INVOICE with sign "Any Sign".  Also we have created a credit memo PROJECT CREDIT MEMO and added to PROJECT INVOICE type.

When we create a negative event the credit note is created under the transactiion type PROJECT INVOICE and not in PROJECT CREDIT MEMO.

Is there any setting missed? We wanted invoices in PROJECT INVOICE type and credit note in PROJECT CREDIT MEMO.

Can anyone guide me on this

Thanks in advance.

Shera