[rules-users] eclipse-jdtcore.jar

I am experiencing a conflict with a deployment: We used WebSphere Application Server 6.0.2.x in our integration testing environment and now the deployed application at a customer site is reporting the following exception: java.lang.NoSuchMethodError: org.eclipse.jdt.internal.compiler.CompilationResult: method getProblems()[Lorg/eclipse/jdt/core/compiler/CategorizedProblem; not found at org.drools.commons.jci.compilers.EclipseJavaCompiler$3.acceptResult(EclipseJ avaCompiler.java(Compiled Code)) at org.eclipse.jdt.internal.compiler.Compiler.handleInternalException(Compiler. java(Compiled Code)) at org.eclipse.jdt.internal.compiler.Compiler.compile(Compiler.java(Compiled Code)) at org.drools.commons.jci.compilers.EclipseJavaCompiler.compile(EclipseJavaComp iler.java(Compiled Code)) at org.drools.commons.jci.compilers.AbstractJavaCompiler.compile(AbstractJavaCo mpiler.java:51) at org.drools.rule.builder.dialect.java.JavaDialect.compileAll(JavaDialect.java :342) Has anyone else comes across this? I am not sure where the JAR comes from because has not version info.