want to save the comment message with user name who commented against to the process id

[ravisankar_vvvs]

I my case i have written the bpmn file and tasks are been assigned using the spring java bean (injected using spring context file) and used in bpmn file as below. i would like to comment message against to each task . can anyone tell me how to do that .
thanks in advance.
<?xml version="1.0" encoding="UTF-8"?>
<definitions xmlns="http://www.omg.org/spec/BPMN/20100524/MODEL" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:activiti="http://activiti.org/bpmn" xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI" xmlnsmgdc="http://www.omg.org/spec/DD/20100524/DC" xmlnsmgdi="http://www.omg.org/spec/DD/20100524/DI" typeLanguage="http://www.w3.org/2001/XMLSchema" expressionLanguage="http://www.w3.org/1999/XPath" targetNamespace="http://www.activiti.org/test">
  <process id="reportWorkFlow" name="reportWorkFlow" isExecutable="true">
    <startEvent id="startevent1" name="Start"></startEvent>
    <sequenceFlow id="flow8" sourceRef="startevent1" targetRef="servicetask1"></sequenceFlow>
    <serviceTask id="servicetask1" name="Service Task" activiti:expression="${reportWorkFlowDAO.newProcess(reportId, reportName, assignee, observer)}" activiti:resultVariableName="workFlowDetails"></serviceTask>
    <sequenceFlow id="flow9" sourceRef="servicetask1" targetRef="usertask1"></sequenceFlow>
    <userTask id="usertask1" name="Assignee Task" activiti:candidateUsers="${workFlowDetails.assignee}" activiti:formKey="managerProposalForm"></userTask>
    <sequenceFlow id="flow4" sourceRef="usertask1" targetRef="usertask2"></sequenceFlow>
    <userTask id="usertask2" name="Owner Task" activiti:candidateGroups="${workFlowDetails.observer}" activiti:formKey="updateUserProposalForm"></userTask>
    <sequenceFlow id="flow5" sourceRef="usertask2" targetRef="exclusivegateway2"></sequenceFlow>
    <exclusiveGateway id="exclusivegateway2" name="Exclusive Gateway"></exclusiveGateway>
    <sequenceFlow id="flow6" sourceRef="exclusivegateway2" targetRef="usertask1">
      <conditionExpression xsi:type="tFormalExpression"><![CDATA[${approved == 'false'}]]></conditionExpression>
    </sequenceFlow>
    <sequenceFlow id="flow7" sourceRef="exclusivegateway2" targetRef="endevent2">
      <conditionExpression xsi:type="tFormalExpression"><![CDATA[${approved == 'true'}]]></conditionExpression>
    </sequenceFlow>
    <endEvent id="endevent2" name="End"></endEvent>
  </process>
</definitions>

[jbarrez]

taskService.addComment ?