unable to convert argument 3 from cdata<struct THCudaTensor*> to cdata<struct THCudaLongTensor*>

[sivagnanamn]

Im using Lua 5.1 and torch7. While trying to execute

th train.lua --cuda --dataset 50000 --hiddenSize 1000

I'm getting the below error:

Dataset stats:
  Vocabulary size: 25931
         Examples: 83632

-- Epoch 1 / 50

/home/siva/torch/install/bin/lua: unable to convert argument 3 from cdata<struct THCudaTensor*> to cdata<struct THCudaLongTensor*>
stack traceback:
        [C]: in function 'v'
        /home/siva/torch/install/share/lua/5.1/nn/THNN.lua:110: in function 'ClassNLLCriterion_updateOutput'
        ...torch/install/share/lua/5.1/nn/ClassNLLCriterion.lua:41: in function <...torch/install/share/lua/5.1/nn/ClassNLLCriterion.lua:29>
        (tail call): ?
        ...rch/install/share/lua/5.1/rnn/SequencerCriterion.lua:55: in function <...rch/install/share/lua/5.1/rnn/SequencerCriterion.lua:39>
        (tail call): ?
        ./seq2seq.lua:74: in function 'train'
        train.lua:85: in main chunk
        [C]: in function 'dofile'
        .../torch/install/lib/luarocks/rocks/trepl/scm-1/bin/th:145: in main chunk
        [C]: ?

[snowluck2345]

same issue...