org.antlr.runtime.CommonToken cannot be cast to org.drools.lang.DroolsToken

I am using Decision table for the condition. I want to compare, two properties of two different class. when creating the object types for that classes in a cell I am facing the problem. I am using drools-compiler5.2.0 FINAL jar file.

The problem is:

Description Resource Path Location Type
Unexpected exception raised while parsing. This is a bug. Please contact the Development team :
java.lang.ClassCastException: org.antlr.runtime.CommonToken cannot be cast to org.drools.lang.DroolsToken
[org.drools.lang.ParserHelper.emit(ParserHelper.java:89), org.drools.lang.DRLParser.fact(DRLParser.java:9214), org.drools.lang.DRLParser.fact_binding(DRLParser.java:8872), org.drools.lang.DRLParser.lhs_pattern(DRLParser.java:8713), org.drools.lang.DRLParser.pattern_source(DRLParser.java:7017), org.drools.lang.DRLParser.lhs_unary(DRLParser.java:5846), org.drools.lang.DRLParser.lhs_and(DRLParser.java:5559), org.drools.lang.DRLParser.lhs_or(DRLParser.java:5249), org.drools.lang.DRLParser.lhs(DRLParser.java:5047), org.drools.lang.DRLParser.normal_lhs_block(DRLParser.java:4953), org.drools.lang.DRLParser.when_part(DRLParser.java:3217), org.drools.lang.DRLParser.rule(DRLParser.java:3009), org.drools.lang.DRLParser.statement(DRLParser.java:746), org.drools.lang.DRLParser.compilation_unit(DRLParser.java:340), org.drools.compiler.DrlParser.compile(DrlParser.java:231), org.drools.compiler.DrlParser.parse(DrlParser.java:71), org.drools.eclipse.DroolsEclipsePlugin.generateParsedResource(DroolsEclipsePlugin.java:416), org.drools.eclipse.DroolsEclipsePlugin.parseXLSResource(DroolsEclipsePlugin.java:310), org.drools.eclipse.builder.DroolsBuilder.parseXLSFile(DroolsBuilder.java:306), org.drools.eclipse.builder.DroolsBuilder.parseResource(DroolsBuilder.java:206), org.drools.eclipse.builder.DroolsBuilder$DroolsBuildVisitor.visit(DroolsBuilder.java:149), org.eclipse.core.internal.resources.Resource$2.visit(Resource.java:112), org.eclipse.core.internal.resources.Resource$1.visitElement(Resource.java:64), org.eclipse.core.internal.watson.ElementTreeIterator.doIteration(ElementTreeIterator.java:82), org.eclipse.core.internal.watson.ElementTreeIterator.doIteration(ElementTreeIterator.java:86), org.eclipse.core.internal.watson.ElementTreeIterator.doIteration(ElementTreeIterator.java:86), org.eclipse.core.internal.watson.ElementTreeIterator.doIteration(ElementTreeIterator.java:86), org.eclipse.core.internal.watson.ElementTreeIterator.doIteration(ElementTreeIterator.java:86), org.eclipse.core.internal.watson.ElementTreeIterator.iterate(ElementTreeIterator.java:127), org.eclipse.core.internal.resources.Resource.accept(Resource.java:74), org.eclipse.core.internal.resources.Resource.accept(Resource.java:110), org.eclipse.core.internal.resources.Resource.accept(Resource.java:94), org.drools.eclipse.builder.DroolsBuilder.fullBuild(DroolsBuilder.java:133), org.drools.eclipse.builder.DroolsBuilder.build(DroolsBuilder.java:95), org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:629), org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42), org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:172), org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:203), org.eclipse.core.internal.events.BuildManager$1.run(BuildManager.java:255), org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42), org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:258), org.eclipse.core.internal.events.BuildManager.basicBuildLoop(BuildManager.java:311), org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:343), org.eclipse.core.internal.events.AutoBuildJob.doBuild(AutoBuildJob.java:144), org.eclipse.core.internal.events.AutoBuildJob.run(AutoBuildJob.java:242), org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)] POC.xls /drools poc/src/main/rules Unknown Drools Error