Jenkins 1522
Testlink upgrade yesterday to 1.9.7
Today upgrade to testlink plugin 3.5
Now, I'm getting the following error:

18:46:05 Preparing TestLink client API.
18:46:05 Using TestLink URL: https://testlink.rsint.net/testlink/lib/api/xmlrpc.php
18:46:05
18:46:05 FATAL: Error verifying developer key: HTTP server returned unexpected status: Not Found
18:46:05 br.eti.kinoshita.testlinkjavaapi.util.TestLinkAPIException: Error verifying developer key: HTTP server returned unexpected status: Not Found
18:46:05 at br.eti.kinoshita.testlinkjavaapi.MiscService.checkDevKey(MiscService.java:63)
18:46:05 at br.eti.kinoshita.testlinkjavaapi.TestLinkAPI.<init>(TestLinkAPI.java:144)
18:46:05 at hudson.plugins.testlink.TestLinkBuilder.getTestLinkSite(TestLinkBuilder.java:253)
18:46:05 at hudson.plugins.testlink.TestLinkBuilder.perform(TestLinkBuilder.java:140)
18:46:05 at hudson.tasks.BuildStepMonitor$1.perform(BuildStepMonitor.java:19)
18:46:05 at hudson.model.AbstractBuild$AbstractBuildExecution.perform(AbstractBuild.java:804)
18:46:05 at hudson.model.Build$BuildExecution.build(Build.java:199)
18:46:05 at hudson.model.Build$BuildExecution.doRun(Build.java:160)
18:46:05 at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:586)
18:46:05 at hudson.model.Run.execute(Run.java:1593)
18:46:05 at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:46)
18:46:05 at hudson.model.ResourceController.execute(ResourceController.java:88)
18:46:05 at hudson.model.Executor.run(Executor.java:247)
18:46:05 Caused by: org.apache.xmlrpc.client.XmlRpcHttpTransportException: HTTP server returned unexpected status: Not Found
18:46:05 at org.apache.xmlrpc.client.XmlRpcSunHttpTransport.getInputStream(XmlRpcSunHttpTransport.java:94)
18:46:05 at org.apache.xmlrpc.client.XmlRpcStreamTransport.sendRequest(XmlRpcStreamTransport.java:152)
18:46:05 at org.apache.xmlrpc.client.XmlRpcHttpTransport.sendRequest(XmlRpcHttpTransport.java:143)
18:46:05 at org.apache.xmlrpc.client.XmlRpcSunHttpTransport.sendRequest(XmlRpcSunHttpTransport.java:69)
18:46:05 at org.apache.xmlrpc.client.XmlRpcClientWorker.execute(XmlRpcClientWorker.java:56)
18:46:05 at org.apache.xmlrpc.client.XmlRpcClient.execute(XmlRpcClient.java:167)
18:46:05 at org.apache.xmlrpc.client.XmlRpcClient.execute(XmlRpcClient.java:158)
18:46:05 at org.apache.xmlrpc.client.XmlRpcClient.execute(XmlRpcClient.java:147)
18:46:05 at br.eti.kinoshita.testlinkjavaapi.BaseService.executeXmlRpcCall(BaseService.java:90)
18:46:05 at br.eti.kinoshita.testlinkjavaapi.MiscService.checkDevKey(MiscService.java:60)
18:46:05 ... 12 more

How can I find the whole stacktrace?

I already found Jenkins-9465, but I do not understand ...
I got this kind of error, when I started with Jenkins and Testlink, the reasons was, that the testlink certificate was missing in the Jenkins keystore.
I checked the keystores, and they look OK to me. The testlink certificate did not change between 1.9.1 and 1.9.7 and it is yet in the Jenkins keystore.
Referring to Jenkins-9465: I cannot access the named testlink URL directly: https://testlink.rsint.net/testlink/lib/api/xmlrpc.php
neither with https, nor with http. I'll get "object not found". But this was already the case before the upgrade.

The problem is blocking, because no regression tests are running any longer.
Thank you for any help!