When I use latest 5.1.1 I'm getting following error when using change-set with DTABLE: <?xml version = '1.0' encoding = 'UTF-8'?> <change-set xmlns='http://drools.org/drools-5.0/change-set' xmlns:xs='http://www.w3.org/2001/XMLSchema-instance' xs:schemaLocation='http://drools.org/drools-5.0/change-set http://anonsvn.jboss.org/repos/labs/labs/jbossrules/trunk/drools-api/src/... <add> <resource source='file:DecisionTables.xls' type="DTABLE"> <decisiontable-conf input-type="XLS" worksheet-name="Sheet1" /> </resource> </add> </change-set> Exception in thread "main" java.lang.NullPointerException at org.drools.decisiontable.DecisionTableProviderImpl.compileStream(DecisionTableProviderImpl.java:26) at org.drools.decisiontable.DecisionTableProviderImpl.loadFromInputStream(DecisionTableProviderImpl.java:19) at org.drools.compiler.DecisionTableFactory.loadFromInputStream(DecisionTableFactory.java:18) at org.drools.compiler.PackageBuilder.addKnowledgeResource(PackageBuilder.java:482) at org.drools.builder.impl.KnowledgeBuilderImpl.add(KnowledgeBuilderImpl.java:28) at org.drools.agent.impl.KnowledgeAgentImpl.createPackageFromResource(KnowledgeAgentImpl.java:637) at org.drools.agent.impl.KnowledgeAgentImpl.addResourcesToKnowledgeBase(KnowledgeAgentImpl.java:889) at org.drools.agent.impl.KnowledgeAgentImpl.rebuildResources(KnowledgeAgentImpl.java:704) at org.drools.agent.impl.KnowledgeAgentImpl.buildKnowledgeBase(KnowledgeAgentImpl.java:584) at org.drools.agent.impl.KnowledgeAgentImpl.applyChangeSet(KnowledgeAgentImpl.java:185) at org.drools.agent.impl.KnowledgeAgentImpl.applyChangeSet(KnowledgeAgentImpl.java:168) at DroolsCompiler.compileChangeSet(DroolsCompiler.java:42) It's similar to JBRULES-2230. I reused solution from comments (on different place) and now it's again working. Attached you can find patch. Can somebody apply to TRUNK? Pavel