Enable Emoji on iOS5
Now you don’t need an App to enable the Emoji keyboard on your iPhone!
All you need to do is the following:
Select INTERNATIONAL KEYBOARDS
Them select ADD NEW KEYBOARD
And scroll to Emoji!
Then when you are writing a text or an email, you select the globe button and choose which icon you want to use!
Only downside is that the Emoji icons can only been seen by iPhones and iPads.