Exception calling tl.addTestCaseToTestPlan method TestLink

[volkertoewe]

Hello,
calling tl.addTestCaseToTestPlan with params {devKey=fe060154c80464be5704598b3822c059, version=1, testprojectid=1233, executionorder=1, testcaseexternalid=1-6, testplanid=1237} I get this exception:
org.apache.xmlrpc.client.XmlRpcClientException: Failed to parse servers response: Expected methodResponse element, got pre
at org.apache.xmlrpc.client.XmlRpcStreamTransport.readResponse(XmlRpcStreamTransport.java:177)
at org.apache.xmlrpc.client.XmlRpcStreamTransport.sendRequest(XmlRpcStreamTransport.java:145)
at org.apache.xmlrpc.client.XmlRpcHttpTransport.sendRequest(XmlRpcHttpTransport.java:94)
at org.apache.xmlrpc.client.XmlRpcSunHttpTransport.sendRequest(XmlRpcSunHttpTransport.java:44)
at org.apache.xmlrpc.client.XmlRpcClientWorker.execute(XmlRpcClientWorker.java:53)
at org.apache.xmlrpc.client.XmlRpcClient.execute(XmlRpcClient.java:166)
...

and the message:
testAddTestCaseToTestPlan(): TestLink1.9.6 (FAILED) => The call to the xml-rpc client failed.
URL: http://testlink.ppi.int/testlink-1.9.6/ ... xmlrpc.php
Method: tl.addTestCaseToTestPlan
Parameters:
devKey='fe060154c80464be5704598b3822c059'
version='1'
testprojectid='1233'
executionorder='1'
testcaseexternalid='1-6'
testplanid='1237'
What has changed in the addTestCaseToTestPlan method? I have no idea what 'Expected methodResponse element, got pre' means.
Thanks in advance for a hint.

[fman]

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