Error using team concert plugin in jenkins pipeline

Hi,
I'm using Team Concert plugin (v 1.2.0.1) in Jenkins to integrate with RTC 5.0.2. It works fine.

I'm starting to use the pipeline plugin and I add the following script (created using the snippet-creation tool):

stage 'SmokeTest'

node('windows'){

    teamconcert([buildDefinition: 'SmokeTestBuild', value: 'buildDefinition'])

    bat '..myscript.bat'

}

but I obtain this not really clear error:

[Pipeline] stage (SmokeTest)
Using the ‘stage’ step without a block argument is deprecated
Entering stage SmokeTest
Proceeding
[Pipeline] node
Running on myserver in C:\JK\workspace\Pipeline test
[Pipeline] {
[Pipeline] teamconcert
RTC : checkout...
[Pipeline] }
[Pipeline] // node
[Pipeline] End of Pipeline
java.lang.NullPointerException
	at com.ibm.team.build.internal.hjplugin.RTCScm.checkout(RTCScm.java:1948)
	at org.jenkinsci.plugins.workflow.steps.scm.SCMStep.checkout(SCMStep.java:109)
	at org.jenkinsci.plugins.workflow.steps.scm.SCMStep$StepExecutionImpl.run(SCMStep.java:83)
	at org.jenkinsci.plugins.workflow.steps.scm.SCMStep$StepExecutionImpl.run(SCMStep.java:73)
	at org.jenkinsci.plugins.workflow.steps.AbstractSynchronousNonBlockingStepExecution$1$1.call(AbstractSynchronousNonBlockingStepExecution.java:52)
	at hudson.security.ACL.impersonate(ACL.java:213)
	at org.jenkinsci.plugins.workflow.steps.AbstractSynchronousNonBlockingStepExecution$1.run(AbstractSynchronousNonBlockingStepExecution.java:49)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)
Finished: FAILURE

Do you know what I can check to make it working properly? The jenkins configuration are the same that works fine with the freestyle jobs.

Thanks,
Michele