Deployment fails with @Singleton annotation and private constructor in EAP 6

Issue

• There are number of classes with private constructors and @Singleton deployed in EAP 6.0.0.

              :
@Startup
public class JBossServiceExample implements JBossServiceExampleMBean {
  private Logger log = Logger.getLogger(this.getClass().getName());

  private JBossServiceExample()
  {
  }
              :

However form EAP 6.0.1 onwards, deployments fail with error:

Caused by: org.jboss.as.server.deployment.DeploymentUnitProcessingException: JBAS014227: EJB JBossServiceExample of type com.redhat.JBossServiceExample must have public default constructor
    at org.jboss.as.ejb3.component.EJBValidationConfigurator.configure(EJBValidationConfigurator.java:62)
    at org.jboss.as.ee.component.deployers.EEModuleConfigurationProcessor.deploy(EEModuleConfigurationProcessor.java:80)