i am creating a custom work item handler which send a complete event to releated user task. it is working in eclipse project but on server it is not working. error is

2015-09-13 03:44:03,436 WARN  (EJB default - 6) Error during command jbpm.custom.workitems.completeTaskWorkItemhandler execution org/kie/services/client/api/RemoteRuntimeEngineFactory
2015-09-13 03:44:03,446 WARN  (EJB default - 6) trimming stacktrace as it's too long : 8074

my java code like follow.

RuntimeEngine engine = RemoteRuntimeEngineFactory.newRestBuilder()
  .addUrl(new URL(ListenEmail.JBPM_HOST))
  .addProcessInstanceId(processId)
  .addUserName(ListenEmail.JBPM_ADMIN_USER)
  .addPassword(ListenEmail.JBPM_ADMIN_USER_PASSS)
  .build();

TaskService taskService = engine.getTaskService();

Libraries are

import org.kie.api.runtime.manager.RuntimeEngine;
import org.kie.services.client.api.RemoteRuntimeEngineFactory;

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>jbpm.custom</groupId>
  <artifactId>workitems</artifactId>
  <version>6.0.0-SNAPSHOT</version>
<dependencies>
  <dependency>
  <groupId>org.jbpm</groupId>
  <artifactId>jbpm-flow</artifactId>
  <version>${jbpm.version}</version>
  </dependency>
  <dependency>
  <groupId>com.sun.mail</groupId>
  <artifactId>javax.mail</artifactId>
  <version>1.5.4</version>
  </dependency>
  <dependency>
  <groupId>junit</groupId>
  <artifactId>junit</artifactId>
  <version>4.12</version>
  </dependency>
  <dependency>
  <groupId>org.kie.remote</groupId>
  <artifactId>kie-remote-client</artifactId>
  <version>${jbpm.version}</version>
  </dependency>
</dependencies>
</project>

jBPM version 6.2.0.Final

Wldfly 8.1.0.Final

Please could you advise ?

Thank you