Class loader problems using remote client

Description of problem:

A project has a process that has a variable of a complex entity defined in data modeler.

Then I try to create a process instance using the remote client. Something like this:

RemoteRestRuntimeFactory remoteRestSessionFactory = new RemoteRestRuntimeFactory( DEPLOYMENT_ID, jbpmURL, "user", "password" );
RemoteRuntimeEngine runtimeEngine = remoteRestSessionFactory.newRuntimeEngine();

KieSession kieSession = runtimeEngine.getKieSession();
Map<String, Object> processVariables = new HashMap<String, Object>();

MyInstance anInst = new MyInstance();
anInst.setProperty1("something");

processVariables.put("myVar", anInst);

ProcessInstance processInstance = kieSession.startProcess( PROCESS_ID, processVariables );

It works ok. But if you build&deploy the project and execute the above code again a problem arises.

In log appears the typical error "A can not be cast to A"

If you restart the server, it works fine again.

Version-Release number of selected component (if applicable):

BPMS GA