OpenXML .docx password protection on Word2003 doesn't work!

Hi There,

We have converted a bunch of Word2003 documents to Word2007 (.docx) which worked great... however, users with Word2003 (400+ users, with compatibility pack installed) are able to Unprotect documents without needing to provide a password!

Even when we reapply document protection with passwords in Word2003, reopening the .docx file still allows users to Unprotect documents.

We have been trying to apply document protection programmatically using C#, but even doing this manually in Word2003 doesn't work!

Is this a bug?  and is there a workaround?

I believe you've found the answer:)