ETO PRP Project Requirement Planning

 I am trying to run PRP for a project with a manufacturing task. There only one level  of BOM; all the components in the BOM have stocking type = H (project purchase); After running the planning report R3483 when I check the messages, I find that there all the message for the component have correctly the project number.

If I insert manually in the part list of  manufcaturing task the same components and I re-run the PRP R3483 all the message for the component doesn't have the project number?

For me ..it's important to maintain the project number also for the component (stocking type H) that I insert manually in the part list.