How do I asynchronously start a process in JBoss BPM Suite 6 using the REST API?

Issue

We have a long running process and when we try to start it using the Remote REST API we have the exception below. We have tried to increase the timeout, but the process sometimes take hours to be finished. What alternatives to we have to start it asynchronously using the remote API?

org.kie.remote.client.api.exception.RemoteCommunicationException: Unable to post request: Error occurred when trying to retrieve response code
    at org.kie.services.client.api.command.AbstractRemoteCommandObject.executeRestCommand(AbstractRemoteCommandObject.java:401)
    at org.kie.services.client.api.command.AbstractRemoteCommandObject.executeCommand(AbstractRemoteCommandObject.java:128)
    at org.kie.services.client.api.command.KieSessionClientCommandObject.startProcess(KieSessionClientCommandObject.java:248)
    at com.redhat.gss.bpms.remote.api.tests.StartProcessTest.doTest(StartProcessTest.java:15)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: org.kie.remote.common.rest.KieRemoteHttpRequestException: Error occurred when trying to retrieve response code
    at org.kie.remote.common.rest.KieRemoteHttpRequest.responseCode(KieRemoteHttpRequest.java:1307)
    at org.kie.remote.common.rest.KieRemoteHttpRequest.post(KieRemoteHttpRequest.java:719)
    at org.kie.services.client.api.command.AbstractRemoteCommandObject.executeRestCommand(AbstractRemoteCommandObject.java:397)
    ... 26 more
Caused by: java.net.SocketTimeoutException: Read timed out
    at java.net.SocketInputStream.socketRead0(Native Method)
    at java.net.SocketInputStream.read(SocketInputStream.java:152)
    at java.net.SocketInputStream.read(SocketInputStream.java:122)
    at java.io.BufferedInputStream.fill(BufferedInputStream.java:235)
    at java.io.BufferedInputStream.read1(BufferedInputStream.java:275)
    at java.io.BufferedInputStream.read(BufferedInputStream.java:334)
    at sun.net.www.http.HttpClient.parseHTTPHeader(HttpClient.java:687)
    at sun.net.www.http.HttpClient.parseHTTP(HttpClient.java:633)
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1323)
    at java.net.HttpURLConnection.getResponseCode(HttpURLConnection.java:468)
    at org.kie.remote.common.rest.KieRemoteHttpRequest.responseCode(KieRemoteHttpRequest.java:1305)
    ... 28 more