If multiple DeployableContainers are in the classpath the exception message is currently incorrect

org.jboss.arquillian.container.test.impl.client.deployment.ValidationException: DeploymentScenario contains targets not matching any defined Container in the registry. _DEFAULT_. Possible causes are: No Deployable Container found on Classpath or your have defined a @org.jboss.arquillian.container.test.api.Deployment with a @org.jboss.arquillian.container.test.api.TargetsContainer value that does not match any found/configured Containers (see arquillian.xml container@qualifier) 
	at org.jboss.arquillian.container.test.impl.client.deployment.DeploymentGenerator.validate(DeploymentGenerator.java:102)
	at org.jboss.arquillian.container.test.impl.client.deployment.DeploymentGenerator.generateDeployment(DeploymentGenerator.java:84)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at org.jboss.arquillian.core.impl.ObserverImpl.invoke(ObserverImpl.java:90)
	at org.jboss.arquillian.core.impl.EventContextImpl.invokeObservers(EventContextImpl.java:99)
	at org.jboss.arquillian.core.impl.EventContextImpl.proceed(EventContextImpl.java:81)
	at org.jboss.arquillian.core.impl.ManagerImpl.fire(ManagerImpl.java:134)
	at org.jboss.arquillian.core.impl.ManagerImpl.fire(ManagerImpl.java:114)
	at org.jboss.arquillian.core.impl.EventImpl.fire(EventImpl.java:67)
	at org.jboss.arquillian.container.test.impl.client.ContainerEventController.execute(ContainerEventController.java:96)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at org.jboss.arquillian.core.impl.ObserverImpl.invoke(ObserverImpl.java:90)
	at org.jboss.arquillian.core.impl.EventContextImpl.invokeObservers(EventContextImpl.java:99)
	at org.jboss.arquillian.core.impl.EventContextImpl.proceed(EventContextImpl.java:81)
	at org.jboss.arquillian.test.impl.TestContextHandler.createClassContext(TestContextHandler.java:68)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at org.jboss.arquillian.core.impl.ObserverImpl.invoke(ObserverImpl.java:90)
	at org.jboss.arquillian.core.impl.EventContextImpl.proceed(EventContextImpl.java:88)
	at org.jboss.arquillian.test.impl.TestContextHandler.createSuiteContext(TestContextHandler.java:54)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at org.jboss.arquillian.core.impl.ObserverImpl.invoke(ObserverImpl.java:90)
	at org.jboss.arquillian.core.impl.EventContextImpl.proceed(EventContextImpl.java:88)
	at org.jboss.arquillian.core.impl.ManagerImpl.fire(ManagerImpl.java:134)
	at org.jboss.arquillian.core.impl.ManagerImpl.fire(ManagerImpl.java:114)
	at org.jboss.arquillian.test.impl.EventTestRunnerAdaptor.beforeClass(EventTestRunnerAdaptor.java:80)
	at org.jboss.arquillian.junit.Arquillian$2.evaluate(Arquillian.java:158)
	at org.jboss.arquillian.junit.Arquillian.multiExecute(Arquillian.java:290)
	at org.jboss.arquillian.junit.Arquillian.access$100(Arquillian.java:45)
	at org.jboss.arquillian.junit.Arquillian$3.evaluate(Arquillian.java:175)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
	at org.jboss.arquillian.junit.Arquillian.run(Arquillian.java:123)
	at org.junit.runner.JUnitCore.run(JUnitCore.java:157)
	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:71)
	at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:199)
	at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:62)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)

   public <T> T onlyOne(Class<T> serviceClass)
   {
      Collection<T> all = all(serviceClass);
      if(all.size() == 1)
      {
         return all.iterator().next();
      }
      if(all.size() > 1)
      {
         throw new IllegalStateException("Multiple service implementations found for " + serviceClass + ". " + toClassString(all)); // <================ GOOD
      }
      return null;
   }

   public void createRegistry(@Observes ArquillianDescriptor event)
   {
      ...
      if(activeConfiguration == null && reg.getContainers().size() == 0)
      {
         try
         {
            DeployableContainer<?> deployableContainer = serviceLoader.onlyOne(DeployableContainer.class);
            if(deployableContainer != null)
            {
               reg.create(new ContainerDefImpl("arquillian.xml").setContainerName("default"), serviceLoader);
            }
         } 
         catch (Exception e) 
         {
            // ignore // <====================================================== BAD
         }
      }

      // export
      registry.set(reg);
   }