Testing the ejb-multi-server quickstart, it fails in this step: mvn exec:java

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[INFO] BUILD FAILURE
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[INFO] Total time: 1.724s
[INFO] Finished at: Thu Sep 12 16:41:41 EDT 2013
[INFO] Final Memory: 12M/146M
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[ERROR] Failed to execute goal org.codehaus.mojo:exec-maven-plugin:1.2.1:java (default-cli) on project jboss-as-ejb-multi-server: The parameters 'mainClass' for goal org.codehaus.mojo:exec-maven-plugin:1.2.1:java are missing or invalid -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/PluginParameterException