Workflow Error - Error in loading configuration for system

Hello experts,

since upgrade to sap netweaver portal 7.30 SP09 we are facing some issues reagarding our workflows / uwl.

I can´t register the system anymore, I`m getting the following error message:

System WORKFLOW_XYZ: Thu Mar 20
14:21:56 CET 2014
(Connector)
:com.sap.netweaver.bc.uwl.connect.ConnectorException:Thu Mar 20 14:21:56 CET
2014
(Connector) :com.sapportals.connector.ConnectorException:Unzulässiger
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So I checked the log files in portal and I found some errors:

User
:<USER.R3_DATASOURCE.MYUSER> getting data from system :
<WORKFLOW_xP2 >: JCO error in reading configuration:Thu Mar 20 14:09:44
CET 2014:com.sapportals.connector.ConnectorException: Unzulässiger
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and

Can someone help me out?

Thanks and best regards,

Mario