Windows Phone 8 issue? or Exchange Sync?

Hey, I wonder if one of you can help and/or any of you are having this issue too: I get my work email on my phone. While in the office I use Outlook 2007 connected to an old Small Business Server 2003 server. I don't have many problems receiving my email on my phone, I do receive them. The problem is that when I read the email on the desktop, my phone does not update to mark that email as "Read" - or at least it doesn't do so in a reasonable timeframe (I think if I leave them for like, 24 hours or so, they will eventually appear as Read on the phone). Even synching manually doesn't seem to do it. I never noticed this problem with my Lumia 800 so I'm assuming it didn't exist... Anyone with the same problem/ideas? Thanks