Mocking SessionContex using mockito causes a ClassNotFoundException

I am starting with unit tests. I've made a change to a class in which I not inject the SessionContext so I can make a lookup when needed.

@Resource
private SessionContext ctx;

Now, in my test, I would like to inject it so I can mock the lookup method:

@Mock
private SessionContext ctx;

But when I run the test, I get:

java.lang.NoClassDefFoundError: javax/xml/rpc/handler/MessageContext at java.lang.Class.getDeclaredMethods0(Native Method) at java.lang.Class.privateGetDeclaredMethods(Class.java:2615) at java.lang.Class.getDeclaredMethods(Class.java:1860) at org.mockito.cglib.core.ReflectUtils.addAllMethods(ReflectUtils.java:349) at org.mockito.cglib.proxy.Enhancer.getMethods(Enhancer.java:427) at org.mockito.cglib.proxy.Enhancer.generateClass(Enhancer.java:457) at org.mockito.cglib.core.DefaultGeneratorStrategy.generate(DefaultGeneratorStrategy.java:25) at org.mockito.cglib.core.AbstractClassGenerator.create(AbstractClassGenerator.java:217) at org.mockito.cglib.proxy.Enhancer.createHelper(Enhancer.java:378) at org.mockito.cglib.proxy.Enhancer.createClass(Enhancer.java:318) at org.mockito.internal.creation.jmock.ClassImposterizer.createProxyClass(ClassImposterizer.java:110) at org.mockito.internal.creation.jmock.ClassImposterizer.imposterise(ClassImposterizer.java:62) at org.powermock.api.mockito.internal.mockcreation.MockCreator.createMethodInvocationControl(MockCreator.java:111) at org.powermock.api.mockito.internal.mockcreation.MockCreator.mock(MockCreator.java:60) at org.powermock.api.mockito.PowerMockito.mock(PowerMockito.java:143) at org.powermock.api.extension.listener.AnnotationEnabler.standardInject(AnnotationEnabler.java:84) at org.powermock.api.extension.listener.AnnotationEnabler.beforeTestMethod(AnnotationEnabler.java:51) at org.powermock.tests.utils.impl.PowerMockTestNotifierImpl.notifyBeforeTestMethod(PowerMockTestNotifierImpl.java:90) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.executeTest(PowerMockJUnit44RunnerDelegateImpl.java:292) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTestInSuper(PowerMockJUnit47RunnerDelegateImpl.java:127) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit47RunnerDelegateImpl$PowerMockJUnit47MethodRunner.executeTest(PowerMockJUnit47RunnerDelegateImpl.java:82) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$PowerMockJUnit44MethodRunner.runBeforesThenTestThenAfters(PowerMockJUnit44RunnerDelegateImpl.java:282) at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:86) at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:49) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.invokeTestMethod(PowerMockJUnit44RunnerDelegateImpl.java:207) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.runMethods(PowerMockJUnit44RunnerDelegateImpl.java:146) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl$1.run(PowerMockJUnit44RunnerDelegateImpl.java:120) at org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:33) at org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:45) at org.powermock.modules.junit4.internal.impl.PowerMockJUnit44RunnerDelegateImpl.run(PowerMockJUnit44RunnerDelegateImpl.java:118) at org.powermock.modules.junit4.common.internal.impl.JUnit4TestSuiteChunkerImpl.run(JUnit4TestSuiteChunkerImpl.java:104) at org.powermock.modules.junit4.common.internal.impl.AbstractCommonPowerMockRunner.run(AbstractCommonPowerMockRunner.java:53) at org.powermock.modules.junit4.PowerMockRunner.run(PowerMockRunner.java:53) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86) at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:675) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192) Caused by: java.lang.ClassNotFoundException: javax.xml.rpc.handler.MessageContext at java.net.URLClassLoader$1.run(URLClassLoader.java:366) at java.net.URLClassLoader$1.run(URLClassLoader.java:355) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:354) at java.lang.ClassLoader.loadClass(ClassLoader.java:425) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308) at java.lang.ClassLoader.loadClass(ClassLoader.java:358) ... 39 more

I find it strange, because I have all the dependencies required (this code works in the real application).

How do I mock and inject the SessionContext using mockito? (I can't change the mocking framework).