The comment tools are grayed out in Reader X on pdf created in Acrobat 8 Pro whether enabled for commenting or not

Creating a PDF from Distiller 8, with No Security method, whether I enable commenting or not, the commenting tools in Reader 10, sticky notes and highlight text, are grayed out.

If I open the file in Reader 10 on the same computer, the information block in Reader 10 says "The file you have opened complies with PDF/A standard and has been opened as read-only to prevent modifications."

If I send the document through the e-mail review, on opening the PDF document in Reader 10 I see the message about reviewing the document and adding comments, but again the sticky notes and highlight text tools are grayed out.

In both cases the document security properties say commenting is allowed.

Help!

Greg Thompson