xcoulon got the following exception when running with the plugins installed that AS requires

Problem is most likely that the class constructor code in (the static blocks) contains:

public static final IProjectFacet WEB_FACET = ProjectFacetsManager.getProjectFacet(FACET_WEB);
public static final IProjectFacet EJB_FACET = ProjectFacetsManager.getProjectFacet(FACET_EJB);
public static final IProjectFacet EAR_FACET = ProjectFacetsManager.getProjectFacet(FACET_EAR);
public static final IProjectFacet UTILITY_FACET = ProjectFacetsManager.getProjectFacet(FACET_UTILITY);
public static final IProjectFacet CONNECTOR_FACET = ProjectFacetsManager.getProjectFacet(FACET_CONNECTOR);
public static final IProjectFacet APP_CLIENT_FACET = ProjectFacetsManager.getProjectFacet(FACET_APP_CLIENT);

public static final IProjectFacet JSF_FACET = ProjectFacetsManager.getProjectFacet(FACET_JSF);
public static final IProjectFacet JPA_FACET = ProjectFacetsManager.getProjectFacet(FACET_JPA);

which my guess says will fail if those facet's are not declared/available.

These facets should be declared as dependencies or the code fixed to handle them not being available.

java.lang.RuntimeException: java.lang.NoClassDefFoundError: Could not initialize class org.jboss.ide.eclipse.as.classpath.core.runtime.WebtoolsProjectJBossClasspathContainerInitializer
at org.eclipse.wst.common.project.facet.ui.internal.FacetsPropertyPage.performOk(FacetsPropertyPage.java:289)
at org.eclipse.jface.preference.PreferenceDialog$13.run(PreferenceDialog.java:964)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:49)
at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175)
at org.eclipse.jface.preference.PreferenceDialog.okPressed(PreferenceDialog.java:944)
at org.eclipse.ui.internal.dialogs.FilteredPreferenceDialog.okPressed(FilteredPreferenceDialog.java:447)
at org.eclipse.jface.preference.PreferenceDialog.buttonPressed(PreferenceDialog.java:233)
at org.eclipse.jface.dialogs.Dialog$2.widgetSelected(Dialog.java:624)
at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:240)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1053)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4163)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3752)
at org.eclipse.jface.window.Window.runEventLoop(Window.java:825)
at org.eclipse.jface.window.Window.open(Window.java:801)
at org.eclipse.ui.dialogs.PropertyDialogAction.run(PropertyDialogAction.java:158)
at org.eclipse.jface.action.Action.runWithEvent(Action.java:498)
at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:584)
at org.eclipse.jface.action.ActionContributionItem.access$2(ActionContributionItem.java:501)
at org.eclipse.jface.action.ActionContributionItem$5.handleEvent(ActionContributionItem.java:411)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1053)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4163)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3752)
at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2696)
at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2660)
at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2494)
at org.eclipse.ui.internal.Workbench$7.run(Workbench.java:674)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:667)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:123)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:344)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
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.eclipse.equinox.launcher.Main.invokeFramework(Main.java:622)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:577)
at org.eclipse.equinox.launcher.Main.run(Main.java:1410)
at org.eclipse.equinox.launcher.Main.main(Main.java:1386)
Caused by: java.lang.NoClassDefFoundError: Could not initialize class org.jboss.ide.eclipse.as.classpath.core.runtime.WebtoolsProjectJBossClasspathContainerInitializer
at org.jboss.ide.eclipse.as.classpath.core.runtime.ProjectRuntimeClasspathProvider.isPrimaryFacet(ProjectRuntimeClasspathProvider.java:86)
at org.jboss.ide.eclipse.as.classpath.core.runtime.ProjectRuntimeClasspathProvider.getClasspathEntries(ProjectRuntimeClasspathProvider.java:70)
at org.eclipse.jst.common.project.facet.core.internal.RuntimeClasspathProvider.getClasspathEntries(RuntimeClasspathProvider.java:51)
at org.eclipse.jst.common.project.facet.core.ClasspathHelper.addClasspathEntries(ClasspathHelper.java:131)
at org.eclipse.jst.j2ee.web.project.facet.WebFacetInstallDelegate.execute(WebFacetInstallDelegate.java:169)
at org.eclipse.wst.common.project.facet.core.internal.FacetedProject.callDelegate(FacetedProject.java:1477)
at org.eclipse.wst.common.project.facet.core.internal.FacetedProject.modifyInternal(FacetedProject.java:441)
at org.eclipse.wst.common.project.facet.core.internal.FacetedProject.mergeChangesInternal(FacetedProject.java:1181)
at org.eclipse.wst.common.project.facet.core.internal.FacetedProject.access$2(FacetedProject.java:1117)
at org.eclipse.wst.common.project.facet.core.internal.FacetedProject$5.run(FacetedProject.java:1099)
at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2344)
at org.eclipse.wst.common.project.facet.core.internal.FacetedProject.mergeChanges(FacetedProject.java:1109)
at org.eclipse.wst.common.project.facet.core.internal.FacetedProjectWorkingCopy.commitChanges(FacetedProjectWorkingCopy.java:2020)
at org.eclipse.wst.common.project.facet.ui.internal.FacetsPropertyPage$4.run(FacetsPropertyPage.java:232)
at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2344)
at org.eclipse.wst.common.project.facet.ui.internal.FacetsPropertyPage$5.run(FacetsPropertyPage.java:246)
at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:121)