I have a potential solution
I noticed that my emails were not coming up on my Hotmail account using the standard email app on my galaxy s2. The ROM I'm using is the Resurrection remix 1.0. My battery used to last only 3/4 hour. Now, when I clear my memory, Exchange services stop running which gives me a nice long battery life. When I start the email app, I can see that on my network bars, I see the up and down arrows constantly on, meaning data is coming in n out the phone. As soon as I close exchange services, these arrows disappear. This clearly shows that there has been a problem with syncing the email to the phone and for some reason its constantly probably trying to fetch these emails. What I did was, delete the email addresses connected to the app, and then connected the emails to the phone again. I put it on WiFi so that all the emails would sync properly, when I see that the arrows on the WiFi signal bars are gone, I knew that the emails were synced properly. Since then I've had no issue with battery drain
Hope This helps!
By the way, this was the first time it had happened to me. I had reinstalled the rom on my phone due to testing out others. I originally had Resurrection 1.0 with all emails connected, no issue at all. Then tested some newer roms, then went back to resurrection 1.0. So i'm sure its just a sync problem. Just delete the connected email and reconnect it the the phone, and let all the emails sync properly in one go!