Wow! This must be a rare issue. Good handful of views and no thoughts from the community. I never have an easy question
Perhaps if you explained what do you mean by "Adobe 10" and told us the version of your OS? Could you edit such files before, or have you always had this problem?
From what you wrote it seems that you are trying to perform a shared review on a PDF rather than having an issue that is exclusive to Adobe Reader / PDF on the local machine.
You may find it useful to browse the Services @ Acrobat.com Forums at:
(particularly if you are using acrobat.com)
If WebDAV or a network server is involved you'd want to discuss the problem with whomever provides support for either.