Service Requests in RTC

Hello All,

I was exploring creating some customizations in RTC (create a total new type of workitem) and since I had a tough time finding right steps I published the same steps (http://www.ibm.com/developerworks/rational/library/custom-work-item-rational-team-concert/index.html).

I have got a query as: Can you please tell me we can customize the work item as a service request or not in the same way ?

Does anybody know what a service request mean here? I am not sure about service request concept in RTC.