How to update a custom attribute value of a workitem using server side API.

 
Hi, 
I wrote a java server side API to update a custom attribute value of a workitem using below code, value is showing in console but value is not updating in work item.
 
public class NcbreleseClass extends AbstractService implements
IOperationParticipant 
{
 
      private IWorkItemCommon fWorkItemCommon;
      public void run(AdvisableOperation operation,
                  IProcessConfigurationElement participantConfig,
                  IParticipantInfoCollector collector, IProgressMonitor monitor)
                  throws TeamRepositoryException 
                  {
                        Object data = operation.getOperationData();
                        ISaveParameter saveParameter = null;
                        
                        if (data instanceof ISaveParameter) 
                        {
                              
                              fWorkItemCommon = getService(IWorkItemCommon.class);
                              saveParameter = (ISaveParameter) data;
                              IAuditable auditable = saveParameter.getNewState();
                              IWorkItem workItem = (IWorkItem)auditable;
                              String type = workItem.getWorkItemType();
                        
                              if (type.equals("projectchangerequest"))
                              {
                      IProjectAreaHandle fprojectArea = workItem.getProjectArea();
                      //info is custom attribute
                      IAttribute infovalue = fWorkItemCommon.findAttribute(fprojectArea,"info",monitor);
                      String value = new String("Update");  
                      workItem.setValue(infovalue,value);
                      Object crValue = workItem.getValue(infovalue);
                        String crstring = crValue.toString();
                        
                              System.out.println("Info Value is updated...."+crstring);
                              
                              }
                        }
                              
                        }
                        
      
      
}
Thanks & Regards 
Sachin Nairy