Sorry for the delay. I've been busy with other project/plug-ins and couldn't find a cycle to work on Jenkins, TestLink or on this plug-in. Sorry.
Since last Wednesday I've been working on these tools, but first I had to release a 1.9.4 testlink-java-api version. Yesterday I released another version of the testlink-java-api, 1.9.5-0. Now I'm working on these issues for 1.9.5/1.9.6.
Thanks for confirming this issue @Fred. I'll take a look on this. Looks like a simple mismatch between the parameters of the testlink-java-api used by the plug-in, and TestLink.
BTW, let me say that today I'm extremely happy, to receive a comment in this plug-in by you. When I wrote this plug-in, the initial version, was highly influenced by your blog entries. I was working on a telecom company, as QA engineer for the first time, and faced the need to integrate my CI jobs with the Test Management team. Not knowing much about test management, your blog was one of the most important resources. So, thank you very much!!!