After upgrade my ipad2 to iOS5, my emoji can't use it

[BabyGirl123]

Hi, anyone can help me ! After upgrade iPad 2 to iOS 5 , when I go in to the previews game chat with my friend when using the emoji app, it's show nothing my chat , just (null) appeared.
Before upgrade my iPad nothing wrong with my emoji app.
It's funny it can use here but can not use it to my previews game like last time (before upgrade).
It's something I not done right ?