How to include username in the taxonomy for taging

Hi

Am working in task manager product ,

Scope of the project is assign task to user's ,

For example ,

one online booking site , 5 developers are involed , and 2 tester ,

Tester find the bug in the site and assign to appropriate developer ,

All are have separate login for the task management ,

, Assume tester A find the issue and that issue is assign to developer x,


How to Include the username in taxonomy list , is there any module there ...

Becoz if we list the username in the list box , then tester can select the employee name from the list box and then send the task to approriate developer ,


Any idea  ,

Thanks



Thanks