Jabber plugin is not showing up in the configure jenkins page.

This is in the log:

Nov 9, 2011 10:21:58 AM hudson.ExtensionFinder$AbstractGuiceFinder$1$1 get
WARNING: Failed to instantiate. Skipping this component
com.google.inject.ProvisionException: Guice provision errors:

1) Error injecting constructor, java.lang.UnsupportedClassVersionError: Bad version number in .class file
at com.thalesgroup.dtkit.metrics.hudson.model.AUnitJunitHudsonTestType$DescriptorImpl.<init>(AUnitJunitHudsonTestType.java:19)

1 error
at com.google.inject.internal.ProviderToInternalFactoryAdapter.get(ProviderToInternalFactoryAdapter.java:52)
at com.google.inject.Scopes$1$1.get(Scopes.java:59)
at hudson.ExtensionFinder$AbstractGuiceFinder$1$1.get(ExtensionFinder.java:252)
at com.google.inject.internal.InternalFactoryToProviderAdapter.get(InternalFactoryToProviderAdapter.java:40)
at com.google.inject.internal.InjectorImpl$4$1.call(InjectorImpl.java:978)
at com.google.inject.internal.InjectorImpl.callInContext(InjectorImpl.java:1024)
at com.google.inject.internal.InjectorImpl$4.get(InjectorImpl.java:974)
at hudson.ExtensionFinder$AbstractGuiceFinder.find(ExtensionFinder.java:221)
at hudson.ExtensionFinder._find(ExtensionFinder.java:110)
at hudson.ClassicPluginStrategy.findComponents(ClassicPluginStrategy.java:289)
at hudson.ExtensionList.load(ExtensionList.java:258)
at hudson.ExtensionList.ensureLoaded(ExtensionList.java:229)
at hudson.ExtensionList.getComponents(ExtensionList.java:147)
at hudson.DescriptorExtensionList.load(DescriptorExtensionList.java:181)
at hudson.ExtensionList.ensureLoaded(ExtensionList.java:229)
at hudson.ExtensionList.iterator(ExtensionList.java:136)
at org.jenkinsci.plugins.xunit.AliasInitializer.addAliases(AliasInitializer.java:23)
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:585)
at hudson.init.InitializerFinder.invoke(InitializerFinder.java:114)
at hudson.init.InitializerFinder$TaskImpl.run(InitializerFinder.java:178)
at org.jvnet.hudson.reactor.Reactor.runTask(Reactor.java:259)
at jenkins.model.Jenkins$5.runTask(Jenkins.java:798)
at org.jvnet.hudson.reactor.Reactor$2.run(Reactor.java:187)
at org.jvnet.hudson.reactor.Reactor$Node.run(Reactor.java:94)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:650)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:675)
at java.lang.Thread.run(Thread.java:595)
Caused by: java.lang.UnsupportedClassVersionError: Bad version number in .class file
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
at com.thalesgroup.dtkit.metrics.hudson.model.AUnitJunitHudsonTestType$DescriptorImpl.<init>(AUnitJunitHudsonTestType.java:19)
at com.thalesgroup.dtkit.metrics.hudson.model.AUnitJunitHudsonTestType$DescriptorImpl$$FastClassByGuice$$3361c067.newInstance(<generated>)
at com.google.inject.internal.cglib.reflect.$FastConstructor.newInstance(FastConstructor.java:40)
at com.google.inject.internal.DefaultConstructionProxyFactory$1.newInstance(DefaultConstructionProxyFactory.java:60)
at com.google.inject.internal.ConstructorInjector.construct(ConstructorInjector.java:85)
at com.google.inject.internal.ConstructorBindingImpl$Factory.get(ConstructorBindingImpl.java:254)
at com.google.inject.internal.ProviderToInternalFactoryAdapter$1.call(ProviderToInternalFactoryAdapter.java:46)
at com.google.inject.internal.InjectorImpl.callInContext(InjectorImpl.java:1031)
at com.google.inject.internal.ProviderToInternalFactoryAdapter.get(ProviderToInternalFactoryAdapter.java:40)
... 29 more
Nov 9, 2011 10:21:55 AM hudson.ExtensionFinder$AbstractGuiceFinder$SezpozModule configure
WARNING: Failed to load hudson.plugins.jabber.im.transport.JabberPublisher
java.lang.UnsupportedClassVersionError: Bad version number in .class file
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2395)
at java.lang.Class.privateGetPublicMethods(Class.java:2519)
at java.lang.Class.getMethods(Class.java:1406)
at hudson.ExtensionFinder$AbstractGuiceFinder$SezpozModule.resolve(ExtensionFinder.java:293)
at hudson.ExtensionFinder$AbstractGuiceFinder$SezpozModule.configure(ExtensionFinder.java:327)
at com.google.inject.AbstractModule.configure(AbstractModule.java:59)
at com.google.inject.spi.Elements$RecordingBinder.install(Elements.java:223)
at com.google.inject.spi.Elements.getElements(Elements.java:101)
at com.google.inject.internal.InjectorShell$Builder.build(InjectorShell.java:133)
at com.google.inject.internal.InternalInjectorCreator.build(InternalInjectorCreator.java:103)
at com.google.inject.Guice.createInjector(Guice.java:95)
at com.google.inject.Guice.createInjector(Guice.java:72)
at hudson.ExtensionFinder$AbstractGuiceFinder.<init>(ExtensionFinder.java:180)
at hudson.ExtensionFinder$GuiceFinder.<init>(ExtensionFinder.java:149)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:494)
at java.lang.Class.newInstance0(Class.java:350)
at java.lang.Class.newInstance(Class.java:303)
at net.java.sezpoz.IndexItem.instance(IndexItem.java:181)
at hudson.ExtensionFinder$Sezpoz.find(ExtensionFinder.java:401)
at hudson.ExtensionFinder._find(ExtensionFinder.java:110)
at hudson.ClassicPluginStrategy.findComponents(ClassicPluginStrategy.java:289)
at hudson.ExtensionList.load(ExtensionList.java:258)
at hudson.ExtensionList.ensureLoaded(ExtensionList.java:229)
at hudson.ExtensionList.iterator(ExtensionList.java:136)
at hudson.ClassicPluginStrategy.findComponents(ClassicPluginStrategy.java:282)
at hudson.ExtensionList.load(ExtensionList.java:258)
at hudson.ExtensionList.ensureLoaded(ExtensionList.java:229)
at hudson.ExtensionList.getComponents(ExtensionList.java:147)
at hudson.DescriptorExtensionList.load(DescriptorExtensionList.java:181)
at hudson.ExtensionList.ensureLoaded(ExtensionList.java:229)
at hudson.ExtensionList.iterator(ExtensionList.java:136)
at org.jenkinsci.plugins.xunit.AliasInitializer.addAliases(AliasInitializer.java:23)
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:585)
at hudson.init.InitializerFinder.invoke(InitializerFinder.java:114)
at hudson.init.InitializerFinder$TaskImpl.run(InitializerFinder.java:178)
at org.jvnet.hudson.reactor.Reactor.runTask(Reactor.java:259)
at jenkins.model.Jenkins$5.runTask(Jenkins.java:798)
at org.jvnet.hudson.reactor.Reactor$2.run(Reactor.java:187)
at org.jvnet.hudson.reactor.Reactor$Node.run(Reactor.java:94)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:650)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:675)
at java.lang.Thread.run(Thread.java:595)
Nov 9, 2011 10:21:54 AM hudson.ExtensionFinder$Sezpoz scout
WARNING: Failed to scout hudson.plugins.jabber.im.transport.JabberPublisher
java.lang.UnsupportedClassVersionError: Bad version number in .class file
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
at hudson.plugins.jabber.im.transport.JabberPublisherDescriptor.<clinit>(JabberPublisherDescriptor.java:73)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:242)
at hudson.ExtensionFinder$Sezpoz.scout(ExtensionFinder.java:439)
at hudson.ClassicPluginStrategy.findComponents(ClassicPluginStrategy.java:283)
at hudson.ExtensionList.load(ExtensionList.java:258)
at hudson.ExtensionList.ensureLoaded(ExtensionList.java:229)
at hudson.ExtensionList.iterator(ExtensionList.java:136)
at hudson.ClassicPluginStrategy.findComponents(ClassicPluginStrategy.java:282)
at hudson.ExtensionList.load(ExtensionList.java:258)
at hudson.ExtensionList.ensureLoaded(ExtensionList.java:229)
at hudson.ExtensionList.getComponents(ExtensionList.java:147)
at hudson.DescriptorExtensionList.load(DescriptorExtensionList.java:181)
at hudson.ExtensionList.ensureLoaded(ExtensionList.java:229)
at hudson.ExtensionList.iterator(ExtensionList.java:136)
at org.jenkinsci.plugins.xunit.AliasInitializer.addAliases(AliasInitializer.java:23)
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:585)
at hudson.init.InitializerFinder.invoke(InitializerFinder.java:114)
at hudson.init.InitializerFinder$TaskImpl.run(InitializerFinder.java:178)
at org.jvnet.hudson.reactor.Reactor.runTask(Reactor.java:259)
at jenkins.model.Jenkins$5.runTask(Jenkins.java:798)
at org.jvnet.hudson.reactor.Reactor$2.run(Reactor.java:187)
at org.jvnet.hudson.reactor.Reactor$Node.run(Reactor.java:94)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:650)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:675)
at java.lang.Thread.run(Thread.java:595)