This is a consequence of the fix for MAVEN-1482: a simple test failure now leads to the following console output:

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BUILD FAILED

Errors stack :
>> Unable to obtain goal [test:test]
>> File...... file:/home/lukas/.maven/cache/maven-test-plugin-1.8.1-SNAPSHOT/plugin.jelly
>> Element... junit
>> Line...... 155
>> Column.... 49
>> Tests failed

You have encountered an unknown error running Maven.
Please help us to correct this problem by following these simple steps:

• read the Maven FAQ at http://maven.apache.org/maven-1.x/faq.html
• run the same command again with the '-e' parameter, eg 'maven -e jar'
• search the maven-user archives for the error at http://www.mail-archive.com/users@maven.apache.org
• post the output of maven -e to JIRA at http://jira.codehaus.org/browse/MAVEN (you must sign up first)
• run 'maven --info' and post the output as the environment to the bug above
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Especially the part 'You have encountered an unknown error...' is not appropriate here.