Automatic bug testing is very crucial for software systems that are widely used. This is especially true when the system is very complex. Unexpected and undesired events could happen due to the presence of bugs. For instance, a web system might take a very long time on a specific query because of the presence of a bug. We cannot expect the creators of the web system to be continually monitoring the system looking for such events. It will greatly benefit the creators of the web system if such events can be automatically detected and if they are notified in a timely fashion. In this paper we report one such bug testing software that we have created for the MnM web system for motif search. MnM is widely used by biologists all over the globe. We feel that the architecture we have employed for our bug testing software is generic and can be applied to other software systems as well. There exist numerous conventional bug testing software tools which are designed to perform only functional or graphical user interface testing.