No.
This problem actually happens when you get disconnected from the game for being AFK, or else leaving the app in the background while running other apps, I have a iPad with iOS 3.2.0 (Notice this version does not haves multi-tasking) and when I lock the device while running the game and I pick it up after a while, I get disconnected and when I try to open the PMs I recived before getting disconnected Im not able to read them.
Obviously Multi-Tasking may cause this, but its not like the origin of the problem.