Vertica Spark Connector throws a java.lang.NullPointerException

I downloaded the Vertica Spark connector and tried the example shown in the connector guide. When I write a DataFrame to Vertica from the Spark-shell using this statement:

df.write.format("com.vertica.spark.datasource.DefaultSource").options(opts).mode(saveMode).save()

I get the following exception. It looks like I have run into a bug in the Vertica connector code. Does anybody know a work around? Thanks.

15/12/14 22:19:08 ERROR TaskSetManager: Task 2 in stage 2.0 failed 4 times; aborting job
org.apache.spark.SparkException: Job aborted due to stage failure: Task 2 in stage 2.0 failed 4 times, most recent failure: Lost task 2.3 in stage 2.0 (TID 93, 10.172.137.138): java.lang.Exception:
Partition[2]: ERROR: Failed while COPYing  data to Vertica.  partition=2. Error message:java.lang.NullPointerException
        at com.vertica.spark.s2v.S2V$$anonfun$1.apply(S2V.scala:199)
        at com.vertica.spark.s2v.S2V$$anonfun$1.apply(S2V.scala:113)
        at org.apache.spark.rdd.RDD$$anonfun$mapPartitionsWithIndex$1$$anonfun$apply$18.apply(RDD.scala:703)
        at org.apache.spark.rdd.RDD$$anonfun$mapPartitionsWithIndex$1$$anonfun$apply$18.apply(RDD.scala:703)
        at org.apache.spark.rdd.MapPartitionsRDD.compute(MapPartitionsRDD.scala:35)
        at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:277)
        at org.apache.spark.rdd.RDD.iterator(RDD.scala:244)
        at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:63)
        at org.apache.spark.scheduler.Task.run(Task.scala:70)
        at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:213)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:745)