Decoding results in sequence of 0s #27

What steps will reproduce the problem?
1. Train on a large vocab corpus. In my case it was 15000 after replacing words 
with freq < 2 to OOV (with 80 states)
2. Decode on the same corpus.
3. Some of the sentences will have a long sequence of 0s (usually towards the 
end)

What is the expected output? What do you see instead?
Expected to see different states for different vocabs. Instead, a long sequence 
of state 0's are seen.

What version of the product are you using? On what operating system?
version 0.6.1 on Ubuntu 12.04

Please provide any additional information below.
You can see the states decoded for the whole corpus below (search for a 
sequence of 0's).