Have you tried more extensive logging or perhaps execution in debug mode?
That will give you many more hints than are available from the default
logging.

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www.geekcode.com
-----BEGIN GEEK CODE BLOCK-----
  Version: 3.1
GCS/cc/e/it d++ s+:+ a-- C++$ UL+++$ E++ W+++$ w--- O---- 
M V- PS PE+++ Y+ PGP- t+ 5 X++ R tv+ b++ DI-- D+ G e++$
h! r++ y++ 
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- A veces creo que hay vida en otros planetas, y a veces creo que
  no. En cualquiera de los dos casos, la conclusión es asombrosa
                                          (Carl Sagan)
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