How to create "signature allowed" documents?

I see several posts about how to sign a pdf from the pdfcreator, but I wonder if I can just make the files created with signature allowed property = true, and sign them later with the adobe reader 9 document , signature menu option.

I mean, imagine you create a pdf report and send it via email to a person who has to sign it and send it signed to a third person.

But, unfortunately, the documents I create with pdfcreator have the signature allowed security property set to false. Is there any way to change this??

Hope I'm explaining myself ok.

"Not allowed" means not possible with Adobe Reader. You can sign these files later.