Partition column in function parameter occurs NPE

create table testQueryCasesOnColumnPartitionedTable (col1 int4, col2 int4, null_col int4) partition by column(key float8)

select pow(key, 2) from testQueryCasesOnColumnPartitionedTable

2014-04-19 10:27:54,455 ERROR querymaster.QueryUnitAttempt (QueryUnitAttempt.java:transition(405)) - FROM 192.168.0.11 >> java.lang.NullPointerException
	at org.apache.tajo.engine.eval.EvalTreeUtil$EvalReplaceVisitor.visitChild(EvalTreeUtil.java:60)
	at org.apache.tajo.engine.eval.EvalTreeUtil$EvalReplaceVisitor.visitChild(EvalTreeUtil.java:44)
	at org.apache.tajo.engine.eval.BasicEvalNodeVisitor.visitDefaultFunctionEval(BasicEvalNodeVisitor.java:154)
	at org.apache.tajo.engine.eval.BasicEvalNodeVisitor.visitFuncCall(BasicEvalNodeVisitor.java:316)
	at org.apache.tajo.engine.eval.BasicEvalNodeVisitor.visitChild(BasicEvalNodeVisitor.java:121)
	at org.apache.tajo.engine.eval.EvalTreeUtil$EvalReplaceVisitor.visitChild(EvalTreeUtil.java:55)
	at org.apache.tajo.engine.eval.EvalTreeUtil.replace(EvalTreeUtil.java:41)
	at org.apache.tajo.engine.planner.physical.SeqScanExec.rewriteColumnPartitionedTableSchema(SeqScanExec.java:115)
	at org.apache.tajo.engine.planner.physical.SeqScanExec.init(SeqScanExec.java:131)
	at org.apache.tajo.engine.planner.physical.UnaryPhysicalExec.init(UnaryPhysicalExec.java:52)
	at org.apache.tajo.engine.planner.physical.StoreTableExec.init(StoreTableExec.java:49)
	at org.apache.tajo.worker.Task.run(Task.java:383)
	at org.apache.tajo.worker.TaskRunner$1.run(TaskRunner.java:391)
	at java.lang.Thread.run(Thread.java:744)