Hi, I'm trying to implement CHANGESET.xml functinlaity through some example.Here is my code KnowledgeBuilder kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder(); //kbuilder.add(ResourceFactory.newUrlResource("file:d:\\rulestest\\changeset.xml"), ResourceType.CHANGE_SET); kbuilder.add(ResourceFactory.newUrlResource( "file:d:\\rulestest\\changeset.xml"), ResourceType.CHANGE_SET ); KnowledgeBuilderErrors errors = kbuilder.getErrors(); if (errors.size() > 0) { for (KnowledgeBuilderError error: errors) { System. err.println(error); But It is generating exception as java.lang.NoSuchFieldError: DESCR at org.drools.compiler.PackageBuilder.addKnowledgeResource(PackageBuilder.java:539) at org.drools.builder.impl.KnowledgeBuilderImpl.add(KnowledgeBuilderImpl.java:28) at com.sample.DroolsTest.readKnowledgeBase(DroolsTest.java:42) at com.sample.DroolsTest.main(DroolsTest.java:24) Im using guvnor 5.2..Could you please suggest me Thanks -- View this message in context: http://drools.46999.n3.nabble.com/No-Such-Field-Error-DESCR-in-implementi... Sent from the Drools: User forum mailing list archive at Nabble.com.