Hi, I am trying to integrate the drools with OSGi. I have included all the drools dependencies in pom.xml. In error stack trace it says error about ruleMemo field present antler osgified jar. "ruleMemo" field lies in org.antlr.runtime.RecognizerSharedState class. can any body help me. Regards, Shelly I am getting the following error: java.lang.NoSuchFieldError: ruleMemo at org.drools.lang.DRLLexer.<init>(DRLLexer.java:96) at org.drools.compiler.DrlParser.getParser(DrlParser.java:207) at org.drools.compiler.DrlParser.parse(DrlParser.java:60) at org.drools.compiler.PackageBuilder.addPackageFromDrl(PackageBuilder.java:165) at com.openwave.neptune.drools.workflow.internal.RuleCreator.createRule(RuleCreator.java:33) at com.openwave.neptune.drools.workflow.internal.ExampleBeanImpl.start(ExampleBeanImpl.java:66) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeCustomInitMethod(AbstractAutowireCapableBeanFactory.java:1529) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1468) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1398) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:512) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:450) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:290) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:287) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:189) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:557) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:842) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:416) at org.springframework.test.AbstractSingleSpringContextTests.createApplicationContext(AbstractSingleSpringContextTests.java:243) at org.springframework.test.AbstractSingleSpringContextTests.loadContextLocations(AbstractSingleSpringContextTests.java:212) at org.springframework.test.AbstractSingleSpringContextTests.loadContext(AbstractSingleSpringContextTests.java:187) at org.springframework.test.AbstractSpringContextTests.getContext(AbstractSpringContextTests.java:140) at org.springframework.test.AbstractSingleSpringContextTests.setUp(AbstractSingleSpringContextTests.java:100) at junit.framework.TestCase.runBare(TestCase.java:128) at org.springframework.test.ConditionalTestCase.runBare(ConditionalTestCase.java:76) at junit.framework.TestResult$1.protect(TestResult.java:106) at junit.framework.TestResult.runProtected(TestResult.java:124) at junit.framework.TestResult.run(TestResult.java:109) at junit.framework.TestCase.run(TestCase.java:120) at junit.framework.TestSuite.runTest(TestSuite.java:230) at junit.framework.TestSuite.run(TestSuite.java:225) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.apache.maven.surefire.junit.JUnitTestSet.execute(JUnitTestSet.java:213) at org.apache.maven.surefire.suite.AbstractDirectoryTestSuite.executeTestSet(AbstractDirectoryTestSuite.java:140) at org.apache.maven.surefire.suite.AbstractDirectoryTestSuite.execute(AbstractDirectoryTestSuite.java:127) at org.apache.maven.surefire.Surefire.run(Surefire.java:177) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.apache.maven.surefire.booter.SurefireBooter.runSuitesInProcess(SurefireBooter.java:345) at org.apache.maven.surefire.booter.SurefireBooter.main(SurefireBooter.java:1009)