Well, compilation of picketlink-authorization-idm-jpa example is OK but deployment into Wildfly 8.1.0.Final give me the following output messages :

09:42:16,063 ERROR [org.jboss.msc.service.fail] (ServerService Thread Pool – 51) MSC000001: Failed to start service jboss.deployment.unit."picketlink-authorization-idm-jpa.war".component.IDMInitializer.START: org.jboss.msc.service.StartException in service jboss.deployment.unit."picketlink-authorization-idm-jpa.war".component.IDMInitializer.START: java.lang.IllegalStateException: JBAS011048: Failed to construct component instance
at org.jboss.as.ee.component.ComponentStartService$1.run(ComponentStartService.java:57) [wildfly-ee-8.1.0.CR2.jar:8.1.0.CR2]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) [rt.jar:1.7.0_65]
at java.util.concurrent.FutureTask.run(FutureTask.java:262) [rt.jar:1.7.0_65]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [rt.jar:1.7.0_65]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [rt.jar:1.7.0_65]
at java.lang.Thread.run(Thread.java:745) [rt.jar:1.7.0_65]
at org.jboss.threads.JBossThread.run(JBossThread.java:122)
Caused by: java.lang.IllegalStateException: JBAS011048: Failed to construct component instance
at org.jboss.as.ee.component.BasicComponent.constructComponentInstance(BasicComponent.java:162) [wildfly-ee-8.1.0.CR2.jar:8.1.0.CR2]
at org.jboss.as.ee.component.BasicComponent.constructComponentInstance(BasicComponent.java:133) [wildfly-ee-8.1.0.CR2.jar:8.1.0.CR2]
at org.jboss.as.ee.component.BasicComponent.createInstance(BasicComponent.java:89) [wildfly-ee-8.1.0.CR2.jar:8.1.0.CR2]
at org.jboss.as.ejb3.component.singleton.SingletonComponent.getComponentInstance(SingletonComponent.java:122)
at org.jboss.as.ejb3.component.singleton.SingletonComponent.start(SingletonComponent.java:137)
at org.jboss.as.ee.component.ComponentStartService$1.run(ComponentStartService.java:54) [wildfly-ee-8.1.0.CR2.jar:8.1.0.CR2]
... 6 more
Caused by: javax.ejb.EJBException: org.picketlink.idm.IdentityManagementException: PLIDM000006: Could not initialize Partition Manager [class org.picketlink.idm.internal.DefaultPartitionManager].
at org.jboss.as.ejb3.tx.CMTTxInterceptor.handleExceptionInOurTx(CMTTxInterceptor.java:190)
at org.jboss.as.ejb3.tx.CMTTxInterceptor.invokeInOurTx(CMTTxInterceptor.java:275)
at org.jboss.as.ejb3.tx.CMTTxInterceptor.requiresNew(CMTTxInterceptor.java:369)
at org.jboss.as.ejb3.tx.LifecycleCMTTxInterceptor.processInvocation(LifecycleCMTTxInterceptor.java:66)
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:309) [jboss-invocation-1.2.1.Final.jar:1.2.1.Final]
at org.jboss.as.weld.injection.WeldInjectionContextInterceptor.processInvocation(WeldInjectionContextInterceptor.java:43)
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:309) [jboss-invocation-1.2.1.Final.jar:1.2.1.Final]
at org.jboss.as.ejb3.component.interceptors.CurrentInvocationContextInterceptor.processInvocation(CurrentInvocationContextInterceptor.java:41)
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:309) [jboss-invocation-1.2.1.Final.jar:1.2.1.Final]
at org.jboss.as.ee.concurrent.ConcurrentContextInterceptor.processInvocation(ConcurrentContextInterceptor.java:45) [wildfly-ee-8.1.0.CR2.jar:8.1.0.CR2]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:309) [jboss-invocation-1.2.1.Final.jar:1.2.1.Final]
at org.jboss.invocation.ContextClassLoaderInterceptor.processInvocation(ContextClassLoaderInterceptor.java:64) [jboss-invocation-1.2.1.Final.jar:1.2.1.Final]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:309) [jboss-invocation-1.2.1.Final.jar:1.2.1.Final]
at org.jboss.invocation.InterceptorContext.run(InterceptorContext.java:326) [jboss-invocation-1.2.1.Final.jar:1.2.1.Final]
at org.jboss.invocation.PrivilegedWithCombinerInterceptor.processInvocation(PrivilegedWithCombinerInterceptor.java:80) [jboss-invocation-1.2.1.Final.jar:1.2.1.Final]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:309) [jboss-invocation-1.2.1.Final.jar:1.2.1.Final]
at org.jboss.invocation.ChainedInterceptor.processInvocation(ChainedInterceptor.java:61) [jboss-invocation-1.2.1.Final.jar:1.2.1.Final]
at org.jboss.as.ee.component.BasicComponent.constructComponentInstance(BasicComponent.java:160) [wildfly-ee-8.1.0.CR2.jar:8.1.0.CR2]
... 11 more
Caused by: org.picketlink.idm.IdentityManagementException: PLIDM000006: Could not initialize Partition Manager [class org.picketlink.idm.internal.DefaultPartitionManager].
at org.picketlink.idm.internal.DefaultPartitionManager.<init>(DefaultPartitionManager.java:235)
at org.picketlink.idm.internal.DefaultPartitionManager.<init>(DefaultPartitionManager.java:156)
at org.picketlink.producer.IdentityManagementProducer.createEmbeddedPartitionManager(IdentityManagementProducer.java:142)
at org.picketlink.producer.IdentityManagementProducer.init(IdentityManagementProducer.java:99)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_65]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_65]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_65]
at java.lang.reflect.Method.invoke(Method.java:606) [rt.jar:1.7.0_65]
at org.jboss.weld.injection.MethodInjectionPoint.invokeWithSpecialValue(MethodInjectionPoint.java:72)
at org.jboss.weld.injection.MethodInjectionPoint.invoke(MethodInjectionPoint.java:66)
at org.jboss.weld.util.Beans.callInitializers(Beans.java:382)
at org.jboss.weld.util.Beans.injectFieldsAndInitializers(Beans.java:370)
at org.jboss.weld.injection.producer.DefaultInjector.inject(DefaultInjector.java:72)
at org.jboss.weld.injection.producer.ResourceInjector.inject(ResourceInjector.java:60)
at org.jboss.weld.injection.producer.DefaultInjector$1.proceed(DefaultInjector.java:66)
at org.jboss.weld.injection.InjectionContextImpl.run(InjectionContextImpl.java:48)
at org.jboss.weld.injection.producer.DefaultInjector.inject(DefaultInjector.java:64)
at org.jboss.weld.injection.producer.BasicInjectionTarget.inject(BasicInjectionTarget.java:90)
at org.jboss.weld.bean.ManagedBean.create(ManagedBean.java:150)
at org.jboss.weld.context.AbstractContext.get(AbstractContext.java:96)
at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:733)
at org.jboss.weld.injection.producer.AbstractMemberProducer.getReceiver(AbstractMemberProducer.java:128)
at org.jboss.weld.injection.producer.AbstractMemberProducer.produce(AbstractMemberProducer.java:148)
at org.jboss.weld.bean.AbstractProducerBean.create(AbstractProducerBean.java:183)
at org.jboss.weld.context.unbound.DependentContextImpl.get(DependentContextImpl.java:69)
at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:733)
at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:789)
at org.jboss.weld.injection.FieldInjectionPoint.inject(FieldInjectionPoint.java:92)
at org.jboss.weld.util.Beans.injectBoundFields(Beans.java:358)
at org.jboss.weld.util.Beans.injectFieldsAndInitializers(Beans.java:369)
at org.jboss.weld.injection.producer.DefaultInjector.inject(DefaultInjector.java:72)
at org.jboss.weld.injection.producer.DefaultInjector$1.proceed(DefaultInjector.java:66)
at org.jboss.weld.injection.InjectionContextImpl.run(InjectionContextImpl.java:48)
at org.jboss.weld.injection.producer.DefaultInjector.inject(DefaultInjector.java:64)
at org.jboss.weld.injection.producer.BasicInjectionTarget.inject(BasicInjectionTarget.java:90)
at org.jboss.as.weld.injection.WeldInjectionContext.inject(WeldInjectionContext.java:39)
at org.jboss.as.weld.injection.WeldInjectionInterceptor.processInvocation(WeldInjectionInterceptor.java:51)
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:309) [jboss-invocation-1.2.1.Final.jar:1.2.1.Final]
at org.jboss.as.ee.component.AroundConstructInterceptorFactory$1.processInvocation(AroundConstructInterceptorFactory.java:28) [wildfly-ee-8.1.0.CR2.jar:8.1.0.CR2]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:309) [jboss-invocation-1.2.1.Final.jar:1.2.1.Final]
at org.jboss.as.weld.injection.WeldInterceptorInjectionInterceptor.processInvocation(WeldInterceptorInjectionInterceptor.java:56)
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:309) [jboss-invocation-1.2.1.Final.jar:1.2.1.Final]
at org.jboss.as.weld.ejb.Jsr299BindingsCreateInterceptor.processInvocation(Jsr299BindingsCreateInterceptor.java:93)
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:309) [jboss-invocation-1.2.1.Final.jar:1.2.1.Final]
at org.jboss.as.ee.component.NamespaceContextInterceptor.processInvocation(NamespaceContextInterceptor.java:50) [wildfly-ee-8.1.0.CR2.jar:8.1.0.CR2]
at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:309) [jboss-invocation-1.2.1.Final.jar:1.2.1.Final]
at org.jboss.as.ejb3.tx.CMTTxInterceptor.invokeInOurTx(CMTTxInterceptor.java:273)
... 27 more
Caused by: org.picketlink.idm.config.SecurityConfigurationException: Error while creating IdentityStore [class org.picketlink.idm.jpa.internal.JPAIdentityStore] instance for configuration [org.picketlink.idm.config.JPAIdentityStoreConfiguration@3bb2ad85].
at org.picketlink.idm.internal.DefaultPartitionManager.createIdentityStore(DefaultPartitionManager.java:827)
at org.picketlink.idm.internal.DefaultPartitionManager.<init>(DefaultPartitionManager.java:220)
... 73 more
Caused by: org.picketlink.idm.config.SecurityConfigurationException: Invalid mapping for type [class org.picketlink.idm.model.basic.GroupMembership]. No entity found with a field annotated with interface org.picketlink.idm.jpa.annotations.Identifier.
at org.picketlink.idm.jpa.internal.JPAIdentityStore.checkIfAnnotationIsDefined(JPAIdentityStore.java:1975)
at org.picketlink.idm.jpa.internal.JPAIdentityStore.validateTypeMapping(JPAIdentityStore.java:1941)
at org.picketlink.idm.jpa.internal.JPAIdentityStore.validateConfiguration(JPAIdentityStore.java:1894)
at org.picketlink.idm.jpa.internal.JPAIdentityStore.setup(JPAIdentityStore.java:149)
at org.picketlink.idm.jpa.internal.JPAIdentityStore.setup(JPAIdentityStore.java:119)
at org.picketlink.idm.internal.DefaultPartitionManager.createIdentityStore(DefaultPartitionManager.java:823)
... 74 more

09:42:16,080 ERROR [org.jboss.as.controller.management-operation] (Controller Boot Thread) JBAS014613: Operation ("deploy") failed - address: ([("deployment" => "picketlink-authorization-idm-jpa.war")]) - failure description: {"JBAS014671: Failed services" => {"jboss.deployment.unit.\"picketlink-authorization-idm-jpa.war\".component.IDMInitializer.START" => "org.jboss.msc.service.StartException in service jboss.deployment.unit.\"picketlink-authorization-idm-jpa.war\".component.IDMInitializer.START: java.lang.IllegalStateException: JBAS011048: Failed to construct component instance
Caused by: java.lang.IllegalStateException: JBAS011048: Failed to construct component instance
Caused by: javax.ejb.EJBException: org.picketlink.idm.IdentityManagementException: PLIDM000006: Could not initialize Partition Manager [class org.picketlink.idm.internal.DefaultPartitionManager].
Caused by: org.picketlink.idm.IdentityManagementException: PLIDM000006: Could not initialize Partition Manager [class org.picketlink.idm.internal.DefaultPartitionManager].
Caused by: org.picketlink.idm.config.SecurityConfigurationException: Error while creating IdentityStore [class org.picketlink.idm.jpa.internal.JPAIdentityStore] instance for configuration [org.picketlink.idm.config.JPAIdentityStoreConfiguration@3bb2ad85].
Caused by: org.picketlink.idm.config.SecurityConfigurationException: Invalid mapping for type [class org.picketlink.idm.model.basic.GroupMembership]. No entity found with a field annotated with interface org.picketlink.idm.jpa.annotations.Identifier."}}

BTW, I tested it with PLINK 2.6.1.Final but I had the same outcome.
I tried to mention it in this ticket with the "Affects Version/s" item but this version was not mentioned. It is probably missing.