TestArena is an open source/freeware tool for test management designed for testers by testers.
Knowing the needs and specificities of testers' work we have prepared (...and we are still developing) a tool for managing tests and test cases.
The main function of TestArena is managing a testing project through tasks assignment. The tool enables you to divide the project up into releases and phases, managing environments and preparing reports. 

Official website: http://testarena.eu
Contact us at http://testarena.eu/contact

Find Installation Guide in the INSTALLATION.txt file.

Polish version of TestArena documentation: http://testarena.pl/dokumentacja

Bug reports can be logged at mantis.testarena.pl/my_view_page.php

As of version 2.0.1, TestArena is released under GPLv2.
Parts of TestArena include libraries from other projects which are used and re-released under their original licence.