Oracle Bulk Load Null Pointer Exception

Hello,

I'm trying to do an Oracle Bulk Load in Kettle. If I enter a stream value that has the possibility of being NULL into one of the fields, I get a NullPointerException when the the step hits that record when creating the data file for sqlldr. I would expect to be able to handle NULL values. However, I'm only able to get the fill data stream to load if I use stream values that have no possibility of being NULL. Here is the error I'm seeing:

2013/04/17 13:25:00 - Oracle Bulk Loader.0 - ERROR (version 4.2.0-stable, build 15748 from 2011-09-08 13.11.42 by buildguy) : Unexpected error
2013/04/17 13:25:00 - Oracle Bulk Loader.0 - ERROR (version 4.2.0-stable, build 15748 from 2011-09-08 13.11.42 by buildguy) : java.lang.NullPointerException

This is happening during the step of creating the sqlldr data file. Any and all help is appreciated.

Thanks!