Examples cannot be run by "mvn exec:java" (Use exec:exec instead)

[lpetrovi@stoker optaplanner-examples]$ mvn exec:java
[INFO] Scanning for projects...
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[INFO] Building OptaPlanner examples 6.2.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------

...

[INFO] --- exec-maven-plugin:1.2.1:java (default-cli) @ optaplanner-examples ---
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[INFO] BUILD FAILURE
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[INFO] Total time: 3.060 s
[INFO] Finished at: 2015-01-31T12:52:02+01:00
[INFO] Final Memory: 43M/513M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.codehaus.mojo:exec-maven-plugin:1.2.1:java (default-cli) on project optaplanner-examples: Unable to parse configuration of mojo org.codehaus.mojo:exec-maven-plugin:1.2.1:java for parameter arguments: Cannot store value into array: ArrayStoreException -> [Help 1]