Jazz Server blocked after programmatically workitem saving

Hi, I have a problem with a server follow-up action (IOperationParticipant).

I'm trying to save a WI change during a state transition (Verified -> Approved)

if (StateChecker.isTransitioning(auditableCommon, saveParameter, CW.getStateId(CW.VERSION_VERIFIED_STATE), CW.getStateId(CW.VERSION_APPROVED_STATE), monitor)) {

						IWorkItem workItemFreshCopy = getFreshCopy(workItem, monitor);

						IWorkItem workingCopy = (IWorkItem) workItemFreshCopy.getWorkingCopy(); 

						IAttribute versionRevision = getWorkItemCommon().findAttribute(workItemFreshCopy.getProjectArea(), WorkItemAttributes.VERSION_REVISION.getStringIdentifier(), monitor);

						Pattern pattern = Pattern.compile("([A-Z]+) draft");

						Matcher matcher = pattern.matcher((String)workItemFreshCopy.getValue(versionRevision));

						if(matcher.find()) {

							if(matcher.groupCount() > 0) {

								String actualVersion = null;



								actualVersion = matcher.group(1);



								workingCopy.setValue(versionRevision, new String(actualVersion));

								IStatus s = getWorkItemService().saveWorkItem2(workingCopy, null, null);

								if (!s.isOK())

									throw new TeamRepositoryException("Errore nel salvataggio. " + s.getMessage());

							}

						}

private IWorkItem getFreshCopy(IWorkItem workItem, IProgressMonitor monitor) throws TeamRepositoryException {

	   	return getWorkItemService().findWorkItemById(workItem.getId(), IWorkItem.FULL_PROFILE, monitor);

	}

The problem is, when I'm calling saveWorkItem2 method, server appear to be blocked (not responding). This sounded strange because if I perform same operation in a different transition, all works fine.

This drives me crazy. Please... can you help me?