Mail with Exchange questions...

I have a couple of minor issues with the Mail app and our companys Exchange server. When I respond to an email on my iPhone, it does not update the status on the mail server. So when I'm back on my laptop at work, emails that I have responded to do not have the little arrow showing I have responded. Is there a setting somewhere or does Apple just not support this?

Secondly, is there anyway to mark an email for follow up in the mail app?

These two issues are annoying to me and should work in a business environment.