Ok so I have been trying to find the answer to this issue for my Thunderbolt and a friends Motorola Droid.
We both see the keyboard become unresponsive in multiple applications (kik messenger, Handscent, Translator and even our web browsers). When the keyboard goes out you push buttons and they vibrate or flash but no text comes out. To fix it I usually have to go into another application and start random typing and it comes back but sometimes I have to go to multiple apps to get it working again. I try killing apps thinking it might be some running causing the issue but that doesn't work either. I can usually get it going again by just switching thru apps til it starts up again.
I have seen this issue with the stock keyboard and also while using swype beta keyboard. My friend uses the stock keyboard on her droid but also uses a swype type of app that I am not sure of the name.
Any thoughts or pointing to the right thread for a fix or answer to this question would be appreciated.