ClassCastException when sending SOAP message for webservice_esb_bpel example

When testing the Webservice_esb_bpel example, I get the following exception after sending the initial example message. The customerOrderAck response is received by the soapui client, but the example continues doing further activities, and one of this activities causes:

14:49:36,706 ERROR [DispatchImpl] Cannot dispatch message
java.io.IOException: Could not transmit message
at org.jboss.ws.core.client.transport.NettyClient.invokeInternal(NettyClient.java:225)
at org.jboss.ws.core.client.transport.NettyClient.invoke(NettyClient.java:119)
at org.jboss.ws.core.client.HTTPRemotingConnection.invoke(HTTPRemotingConnection.java:150)
at org.jboss.ws.core.client.SOAPProtocolConnectionHTTP.invoke(SOAPProtocolConnectionHTTP.java:69)
at org.jboss.ws.core.jaxws.client.DispatchImpl.invokeInternalSOAP(DispatchImpl.java:247)
at org.jboss.ws.core.jaxws.client.DispatchImpl.invokeInternal(DispatchImpl.java:170)
at org.jboss.ws.core.jaxws.client.DispatchImpl.invoke(DispatchImpl.java:133)
at org.jboss.soa.bpel.runtime.ws.WebServiceClient$1$1.call(WebServiceClient.java:138)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)
Caused by: java.lang.ClassCastException: java.util.ArrayList cannot be cast to java.lang.Integer
at org.jboss.ws.core.soap.SOAPMessageUnMarshallerHTTP.read(SOAPMessageUnMarshallerHTTP.java:66)
at org.jboss.ws.core.client.transport.NettyClient.invokeInternal(NettyClient.java:189)
... 12 more
14:49:36,707 ERROR [WebServiceClient] WS invocation failed
javax.xml.ws.WebServiceException: Cannot dispatch message
at org.jboss.ws.core.jaxws.client.DispatchImpl.handleInvokeException(DispatchImpl.java:379)
at org.jboss.ws.core.jaxws.client.DispatchImpl.invoke(DispatchImpl.java:137)
at org.jboss.soa.bpel.runtime.ws.WebServiceClient$1$1.call(WebServiceClient.java:138)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)
Caused by: java.io.IOException: Could not transmit message
at org.jboss.ws.core.client.transport.NettyClient.invokeInternal(NettyClient.java:225)
at org.jboss.ws.core.client.transport.NettyClient.invoke(NettyClient.java:119)
at org.jboss.ws.core.client.HTTPRemotingConnection.invoke(HTTPRemotingConnection.java:150)
at org.jboss.ws.core.client.SOAPProtocolConnectionHTTP.invoke(SOAPProtocolConnectionHTTP.java:69)
at org.jboss.ws.core.jaxws.client.DispatchImpl.invokeInternalSOAP(DispatchImpl.java:247)
at org.jboss.ws.core.jaxws.client.DispatchImpl.invokeInternal(DispatchImpl.java:170)
at org.jboss.ws.core.jaxws.client.DispatchImpl.invoke(DispatchImpl.java:133)
... 6 more
Caused by: java.lang.ClassCastException: java.util.ArrayList cannot be cast to java.lang.Integer
at org.jboss.ws.core.soap.SOAPMessageUnMarshallerHTTP.read(SOAPMessageUnMarshallerHTTP.java:66)
at org.jboss.ws.core.client.transport.NettyClient.invokeInternal(NettyClient.java:189)
... 12 more