how to resolve "UndeclaredThrowableException"

I developed one consumer application and tested it on my system, everything is working fine and I provided EAR file to testing team.But when they try to access My application most of the functionalities are working fine, Some functionality they getting "UndeclaredThrowableException". Please find the below error stack trace. I’m getting:

java.lang.reflect.UndeclaredThrowableException

    at $Proxy2.setQuestionsAnsweredFailures(Unknown Source)

    at DACTest.main(DACTest.java:59)

Caused by: java.lang.ClassNotFoundException: com.toyota.security.tbg2.dispatch.LDAPOperationException

    at org.jboss.remoting.serialization.ClassLoaderUtility.loadClass(ClassLoaderUtility.java:103)

    at org.jboss.remoting.loading.RemotingClassLoader.loadClass(RemotingClassLoader.java:86)

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

    at java.lang.Class.forName(Class.java:247)

    at org.jboss.remoting.loading.ObjectInputStreamWithClassLoader.resolveClass(ObjectInputStreamWithClassLoader.java:179)

    at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1574)

    at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1495)

Please provide any suggestions to resolve this issue.