pig + ES problem

gistfile1.txt

index.pig:

    register /home/foo/elasticsearch-hadoop-1.3.0.M3/dist/elasticsearch-hadoop-pig-1.3.0.M3.jar
    a = load '$files' using PigStorage() as (json:chararray);
    store a into '$index' using org.elasticsearch.hadoop.pig.EsStorage('es.input.json=true','es.nodes=hadoop.bla:9200');

$  pig -param files=`cat filelist | tr "\n" "," | sed -e 's/,$//'` -param index=hadooptest/t -f index.pig



Pig Stack Trace
---------------
ERROR 2998: Unhandled internal error. Found interface org.apache.hadoop.mapreduce.JobContext, but class was expected

java.lang.IncompatibleClassChangeError: Found interface org.apache.hadoop.mapreduce.JobContext, but class was expected
        at org.elasticsearch.hadoop.mr.EsOutputFormat.checkOutputSpecs(EsOutputFormat.java:311)
        at org.apache.pig.newplan.logical.rules.InputOutputFileValidator$InputOutputFileVisitor.visit(InputOutputFileValidator.java:80)
        at org.apache.pig.newplan.logical.relational.LOStore.accept(LOStore.java:66)
        at org.apache.pig.newplan.DepthFirstWalker.depthFirst(DepthFirstWalker.java:64)
        at org.apache.pig.newplan.DepthFirstWalker.depthFirst(DepthFirstWalker.java:66)
        at org.apache.pig.newplan.DepthFirstWalker.depthFirst(DepthFirstWalker.java:66)
        at org.apache.pig.newplan.DepthFirstWalker.walk(DepthFirstWalker.java:53)
        at org.apache.pig.newplan.PlanVisitor.visit(PlanVisitor.java:52)
        at org.apache.pig.newplan.logical.rules.InputOutputFileValidator.validate(InputOutputFileValidator.java:45)
        at org.apache.pig.backend.hadoop.executionengine.HExecutionEngine.compile(HExecutionEngine.java:285)
        at org.apache.pig.PigServer.compilePp(PigServer.java:1324)
        at org.apache.pig.PigServer.executeCompiledLogicalPlan(PigServer.java:1249)
        at org.apache.pig.PigServer.execute(PigServer.java:1241)
        at org.apache.pig.PigServer.executeBatch(PigServer.java:335)
        at org.apache.pig.tools.grunt.GruntParser.executeBatch(GruntParser.java:137)
        at org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:198)
        at org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:170)
        at org.apache.pig.tools.grunt.Grunt.exec(Grunt.java:84)
        at org.apache.pig.Main.run(Main.java:475)
        at org.apache.pig.Main.main(Main.java:157)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at org.apache.hadoop.util.RunJar.main(RunJar.java:208)
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