Error when using deployClusterSetup.py

I tried to install the setup application on the node running the deployment manager by using the deployClusterSetup.py script.

Everything seemed to go okay until this last step:

ADMA5001I: The application binaries are saved in /opt/IBM/WebSphere/AppServer/profiles/DM/wstemp/Script12888a0be79/workspace/cells/DMCell/applications/com.ibm.ram.repository.setup.web.ear.ear/com.ibm.ram.repository.setup.web.ear.ear
ADMA5005I: The application com.ibm.ram.repository.setup.web.ear is configured in the WebSphere Application Server repository.
SECJ0400I: Successfuly updated the application com.ibm.ram.repository.setup.web.ear with the appContextIDForSecurity information.
ADMA5011I: The cleanup of the temp directory for application com.ibm.ram.repository.setup.web.ear is complete.
ADMA5013I: Application com.ibm.ram.repository.setup.web.ear installed successfully.
Wait for 2 minutes to ensure application is available before starting it
Starting application
WASX7017E: Exception received while running file "/tmp/RAMinstall/conf/bin/deployClusterSetup.py"; exception information: com.ibm.ws.scripting.ScriptingException: WASX7025E: Error found in String "WebSphere:name=ApplicationManager,process=RAMServer1,platform=proxy,node=RAMNode1,version=6.1.0.29,type=ApplicationManager,mbeanIdentifier=ApplicationManager,cell=DMCell,spec=1.0
WebSphere:name=ApplicationManager,process=dmgr,platform=proxy,node=DMNode,version=6.1.0.29,type=ApplicationManager,mbeanIdentifier=ApplicationManager,cell=DMCell,spec=1.0"; cannot create ObjectName.

Why does this error happen?