there is an issue with fault injection api in the latest testapi version (0.6). unfortunately the testapi project on codeplex doesn't seem to be actively maintained any more. so i'm working on creating an new project on codeplex for managed fault injeciton only. the new project will have full functionality instead of the current limited version.
before the new project goes live, please use testapi 0.5 version for fault injeciton.