IBM Rational Clearquest 

IBM® Rational® ClearQuest® a bug tracking system which provides flexible defect and change tracking, process automation, reporting and lifecycle traceability for better visibility and control of the development lifecycle.

Main features:

- Flexible, customizable and automated workflows provide repeatable, enforceable and predictable processes

- An out-of-the-box Application Lifecycle Management (ALM) template provides a solid foundation for ALM best practices

- Real-time reporting and metrics improves project visibility and decision making

- Access control, electronic signatures, repeatable processes and audit trails simplify compliance management

- Scales to fit any size team from small workgroups to distributed enterprise teams to support evolving organizational needs

- Integration with requirements, development, build, test, deployment and portfolio management tools facilitates rapid response to change

- Operating systems supported: AIX, HP-UX, Linux, Solaris (Sun microsystems), Windows