Please find the error and advise me

javax.naming.NamingException: Could not load ejb proxy class com.istana.schedule.feature.Manager/HelloWorldSessionBean//HelloWorldBean!com.ibytecode.business.HelloWorld [Root exception is java.lang.ClassNotFoundException: com.istana.schedule.feature.Manager/HelloWorldSessionBean//HelloWorldBean!com.ibytecode.business.HelloWorld]

  at org.jboss.ejb.client.naming.ejb.EjbNamingContext.createEjbProxy(EjbNamingContext.java:108)

  at org.jboss.ejb.client.naming.ejb.EjbNamingContext.lookup(EjbNamingContext.java:96)

  at javax.naming.InitialContext.lookup(InitialContext.java:411)

  at com.ibytecode.client.EJBApplicationClient.doLookup(EJBApplicationClient.java:26)

  at com.ibytecode.client.EJBApplicationClient.main(EJBApplicationClient.java:13)

Caused by: java.lang.ClassNotFoundException: com.istana.schedule.feature.Manager/HelloWorldSessionBean//HelloWorldBean!com.ibytecode.business.HelloWorld

  at java.lang.Class.forName0(Native Method)

  at java.lang.Class.forName(Class.java:274)

  at org.jboss.ejb.client.naming.ejb.EjbNamingContext.createEjbProxy(EjbNamingContext.java:106)

  ... 4 more

Exception in thread "main" java.lang.NullPointerException

  at com.ibytecode.client.EJBApplicationClient.main(EJBApplicationClient.java:14)