"ClassNotFoundException: org.jboss.system.server.jmx.MBeanServerBuilderImpl" error when connecting CLI to JBoss EAP

Issue

• We have this error when we try to connect to JBoss EAP 6 instance with the CLI:

  JBoss CLI server state: Exception in thread "main" javax.management.JMRuntimeException: Failed to load MBeanServerBuilder class org.jboss.system.server.jmx.MBeanServerBuilderImpl: java.lang.ClassNotFoundException: org.jboss.system.server.jmx.MBeanServerBuilderImpl from [Module "org.jboss.as.cli:main" from local module loader @2d342ba4 (finder: local module finder @3c1d332b (roots: /opt/jboss/modules,/opt/jboss/modules/system/layers/base))]
          at javax.management.MBeanServerFactory.checkMBeanServerBuilder(MBeanServerFactory.java:480)
          at javax.management.MBeanServerFactory.getNewMBeanServerBuilder(MBeanServerFactory.java:511)
          at javax.management.MBeanServerFactory.newMBeanServer(MBeanServerFactory.java:298)
          at javax.management.MBeanServerFactory.createMBeanServer(MBeanServerFactory.java:213)
          at javax.management.MBeanServerFactory.createMBeanServer(MBeanServerFactory.java:174)
          at sun.management.ManagementFactory.createPlatformMBeanServer(ManagementFactory.java:302)
          at java.lang.management.ManagementFactory.getPlatformMBeanServer(ManagementFactory.java:504)
          at org.jboss.modules.ModuleLoader$RealMBeanReg$1.run(ModuleLoader.java:888)
          at org.jboss.modules.ModuleLoader$RealMBeanReg$1.run(ModuleLoader.java:886)
          at java.security.AccessController.doPrivileged(Native Method)
          at org.jboss.modules.ModuleLoader$RealMBeanReg.<init>(ModuleLoader.java:886)
          at org.jboss.modules.ModuleLoader$TempMBeanReg.installReal(ModuleLoader.java:870)
          at org.jboss.modules.ModuleLoader.installMBeanServer(ModuleLoader.java:210)
          at org.jboss.modules.Main.main(Main.java:408)
  Caused by: java.lang.ClassNotFoundException: org.jboss.system.server.jmx.MBeanServerBuilderImpl from [Module "org.jboss.as.cli:main" from local module loader @2d342ba4 (finder: local module finder @3c1d332b (roots: /opt/jboss/modules,/opt/jboss/modules/system/layers/base))]
          at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:196)
          at org.jboss.modules.ConcurrentClassLoader.performLoadClassUnchecked(ConcurrentClassLoader.java:444)
          at org.jboss.modules.ConcurrentClassLoader.performLoadClassChecked(ConcurrentClassLoader.java:432)
          at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:374)
          at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:119)
          at javax.management.MBeanServerFactory.loadBuilderClass(MBeanServerFactory.java:423)
          at javax.management.MBeanServerFactory.checkMBeanServerBuilder(MBeanServerFactory.java:465)
          ... 13 more