axios spatial operation extension 1.2 for uDIG 1.1.1 error: bad version number in .class file

I am not able to use the axios spatial operations extension for uDIG 1.1.1
I get the following error:

java.lang.UnsupportedClassVersionError: Bad version number in .class file
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:675)
at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.defineClass(DefaultClassLoader.java:161)
at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.defineClass(ClasspathManager.java:501)
at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findClassImpl(ClasspathManager.java:471)
at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findLocalClassImpl(ClasspathManager.java:430)
at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findLocalClass(ClasspathManager.java:413)
at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.findLocalClass(DefaultClassLoader.java:189)
at org.eclipse.osgi.framework.internal.core.BundleLoader.findLocalClass(BundleLoader.java:340)
at org.eclipse.osgi.framework.internal.core.BundleLoader.findClassInternal(BundleLoader.java:408)
at org.eclipse.osgi.framework.internal.core.BundleLoader.findClass(BundleLoader.java:369)
at org.eclipse.osgi.framework.internal.core.BundleLoader.findClass(BundleLoader.java:357)
at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:83)
at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
at org.eclipse.osgi.framework.internal.core.BundleLoader.loadClass(BundleLoader.java:289)
at org.eclipse.osgi.framework.internal.core.BundleHost.loadClass(BundleHost.java:227)
at org.eclipse.osgi.framework.internal.core.AbstractBundle.loadClass(AbstractBundle.java:1269)
at org.eclipse.core.internal.registry.osgi.RegistryStrategyOSGI.createExecutableExtension(RegistryStrategyOSGI.java:160)
at org.eclipse.core.internal.registry.ExtensionRegistry.createExecutableExtension(ExtensionRegistry.java:788)
at org.eclipse.core.internal.registry.ConfigurationElement.createExecutableExtension(ConfigurationElement.java:243)
at org.eclipse.core.internal.registry.ConfigurationElementHandle.createExecutableExtension(ConfigurationElementHandle.java:51)
at org.eclipse.ui.internal.WorkbenchPlugin$1.run(WorkbenchPlugin.java:252)
at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:67)
at org.eclipse.ui.internal.WorkbenchPlugin.createExtension(WorkbenchPlugin.java:248)
at org.eclipse.ui.internal.registry.ViewDescriptor.createView(ViewDescriptor.java:69)
at org.eclipse.ui.internal.ViewReference.createPartHelper(ViewReference.java:327)
at org.eclipse.ui.internal.ViewReference.createPart(ViewReference.java:227)
at org.eclipse.ui.internal.WorkbenchPartReference.getPart(WorkbenchPartReference.java:592)
at org.eclipse.ui.internal.PartPane.setVisible(PartPane.java:299)
at org.eclipse.ui.internal.ViewPane.setVisible(ViewPane.java:531)
at org.eclipse.ui.internal.presentations.PresentablePart.setVisible(PresentablePart.java:179)
at org.eclipse.ui.internal.presentations.util.PresentablePartFolder.select(PresentablePartFolder.java:268)
at org.eclipse.ui.internal.presentations.util.LeftToRightTabOrder.select(LeftToRightTabOrder.java:65)
at org.eclipse.ui.internal.presentations.util.TabbedStackPresentation.selectPart(TabbedStackPresentation.java:400)
at org.eclipse.ui.internal.PartStack.refreshPresentationSelection(PartStack.java:1256)
at org.eclipse.ui.internal.PartStack.createControl(PartStack.java:668)
at org.eclipse.ui.internal.PartStack.createControl(PartStack.java:576)
at org.eclipse.ui.internal.PartSashContainer.createControl(PartSashContainer.java:564)
at org.eclipse.ui.internal.PerspectiveHelper.activate(PerspectiveHelper.java:270)
at org.eclipse.ui.internal.Perspective.onActivate(Perspective.java:931)
at org.eclipse.ui.internal.WorkbenchPage.onActivate(WorkbenchPage.java:2515)
at org.eclipse.ui.internal.WorkbenchWindow$23.run(WorkbenchWindow.java:2837)
at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:67)
at org.eclipse.ui.internal.WorkbenchWindow.setActivePage(WorkbenchWindow.java:2818)
at org.eclipse.ui.internal.WorkbenchWindow$17.runWithException(WorkbenchWindow.java:2135)
at org.eclipse.ui.internal.StartupThreading$StartupRunnable.run(StartupThreading.java:31)
at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:129)
at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:3214)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:2954)
at org.eclipse.ui.application.WorkbenchAdvisor.openWindows(WorkbenchAdvisor.java:801)
at org.eclipse.ui.internal.Workbench$25.runWithException(Workbench.java:1342)
at org.eclipse.ui.internal.StartupThreading$StartupRunnable.run(StartupThreading.java:31)
at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:129)
at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:3214)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:2954)
at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2309)
at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2219)
at org.eclipse.ui.internal.Workbench$4.run(Workbench.java:466)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:289)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:461)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
at net.refractions.udig.internal.ui.UDIGApplication.start(Unknown Source)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:169)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:106)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:76)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:363)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:176)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

Thanks for any help that can be provided.
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:592)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:508)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:447)
at org.eclipse.equinox.launcher.Main.run(Main.java:1173)