Sometimes, it seems as if lawsuits are as inseparable from the open source ecosystem as unshaven, geeky developers. In the past, Linux has even had to defend its very name in the courts. But open source advocates have a good record of winning such cases, and they chalked up another important victory last week in a fight that pit Red Hat (NYSE: RHT) and Rackspace (NYSE: RAX) against a foe with a long history of litigation against technology giants.