Steps to reproduce this issue:

1. Create a new project
2. Create InputField ( Create-> UI -> Input Field )
3. Play the scene
4. Enter 2 symbols ( for example 09 )
5. Now select first symbol with a mouse
6. Change it to something else ( for example 1 )
7. Notice now you have only one symbol instead of 2
8. Deselect and Reselect input field and 2 symbols reappear

Workaround: Problem does not reproduce when Line Type is 'MultiLine Submit' or 'MultiLine NewLine'

Captured repro: http://screencast.com/t/ppdMMANvX6Ds