The following error is reported when using the Jenkins TestLink plugin v2.2 with TestLink 1.9.2:

Updating 1 test case(s) execution status.
Updating automated test case DefaultInitialization with execution status Passed.
FATAL: Failed to update TestLink test results: (reportTCResult) - Parameter platformname OR platformid is required, but has not been provided.
br.eti.kinoshita.testlinkjavaapi.TestLinkAPIException: (reportTCResult) - Parameter platformname OR platformid is required, but has not been provided
at br.eti.kinoshita.testlinkjavaapi.BaseService.checkResponseError(BaseService.java:119)
at br.eti.kinoshita.testlinkjavaapi.BaseService.executeXmlRpcCall(BaseService.java:92)
at br.eti.kinoshita.testlinkjavaapi.TestCaseService.reportTCResult(TestCaseService.java:634)
at br.eti.kinoshita.testlinkjavaapi.TestLinkAPI.reportTCResult(TestLinkAPI.java:953)
at hudson.plugins.testlink.TestLinkService.updateTestCasesAndUploadAttachments(TestLinkService.java:166)
at hudson.plugins.testlink.TestLinkBuilder.perform(TestLinkBuilder.java:538)
at hudson.tasks.BuildStepMonitor$1.perform(BuildStepMonitor.java:19)
at hudson.model.AbstractBuild$AbstractRunner.perform(AbstractBuild.java:649)
at hudson.model.Build$RunnerImpl.build(Build.java:177)
at hudson.model.Build$RunnerImpl.doRun(Build.java:139)
at hudson.model.AbstractBuild$AbstractRunner.run(AbstractBuild.java:423)
at hudson.model.Run.run(Run.java:1362)
at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:46)
at hudson.model.ResourceController.execute(ResourceController.java:88)
at hudson.model.Executor.run(Executor.java:145)
ERROR: Failed to update TestLink test results: (reportTCResult) - Parameter platformname OR platformid is required, but has not been provided.
Finished: FAILURE

From the response to tl.getTestCasesForTestPlan, the platform name is correctly returned in the member with name "platform_name". In the tl.reportTCResult call, a member called platformname is specified with a value of <ex:nil/>. The platform ID member has the same problem: platformid is specified with a value of <ex:nil/> where the information is provided in platform_id.