Pause test time through ajax timer

Hi, I need a very small chunk which i can used in my test application. Its about pausing a time during test using ajax timer in asp.net page. The scenario is like this: 1: User Enters test time in terms of minutes and seconds. 2: The application redirects to test form which shows the remaining duration at real time through asp.net ajax timer. 3: There is a pause button on same test form and when user press it, the time should be paused and when user press resume test button it should be start again from the last time. From the above three features I only need third feature. We will send the existing work to winner to accomodate third option there. It should not take more then an hour for a good programmer. Thanks..