Cannot create confirmation for PO service in ECC

Dear SAP gurus,

We're using SRM 7.01 and ECC 6.05. We are using classic scenario, but not some requisition and PO are created ONLY in ECC. My question is, is it possible for us to create confirmation in SRM for PO service (created in ECC) which originating from a PR service (also created in ECC)?

Appreciate if you can confirm this.

Best regards,

John