some unit tests from dna-common failed when, I changed locale variable to "de_DE"

mac2008:~ sp$ locale
LANG="de_DE"
LC_COLLATE="de_DE"
LC_CTYPE="de_DE"
LC_MESSAGES="de_DE"
LC_MONETARY="de_DE"
LC_NUMERIC="de_DE"
LC_TIME="de_DE"
LC_ALL=

Failed tests:
shouldProvideIdempotentInitialization(org.jboss.dna.common.i18n.I18nTest)
shouldHaveTextMatchingLocalizationFilePropertyValue(org.jboss.dna.common.i18n.I18nTest)
shouldFailIfTooFewArgumentsSuppliedToText(org.jboss.dna.common.i18n.I18nTest)
shouldFailIfTooManyArgumentsSuppliedToText(org.jboss.dna.common.i18n.I18nTest)
shouldContainArgumentsInRightOrderInText(org.jboss.dna.common.i18n.I18nTest)
shouldAllowReuseOfArgumentsInText(org.jboss.dna.common.i18n.I18nTest)
shouldContainTextForDefaultLocaleIfMissingLocalizationForSuppliedLocale(org.jboss.dna.common.i18n.I18nTest)
shouldReturnProgressStatusWithCorrectMessageAfterTaskIsBegun(org.jboss.dna.common.monitor.SimpleProgressMonitorTest)
shouldReturnProgressStatusWithCorrectMessageAndSubstitutedParametersAfterTaskIsBegun(org.jboss.dna.common.monitor.SimpleProgressMonitorTest)
shouldHaveToStringThatIncludesPercentage(org.jboss.dna.common.monitor.ProgressStatusTest)
shouldRepresentTimeInProperFormat(org.jboss.dna.common.math.DurationTest)

Tests run: 444, Failures: 11, Errors: 0, Skipped: 0

Trace:
-------------------------------------------------------------------------------
Test set: org.jboss.dna.common.i18n.I18nTest
-------------------------------------------------------------------------------
Tests run: 41, Failures: 7, Errors: 0, Skipped: 0, Time elapsed: 0.21 sec <<< FAILURE!
shouldProvideIdempotentInitialization(org.jboss.dna.common.i18n.I18nTest) Time elapsed: 0.006 sec <<< FAILURE!
java.lang.AssertionError:
Expected: is "test"
got: "<Problems were encountered while localizing internationalization class org.jboss.dna.common.i18n.I18nTest$TestI18n to locale \"de_DE\" >"

at org.junit.Assert.assertThat(Assert.java:502)
at org.junit.Assert.assertThat(Assert.java:492)
at org.jboss.dna.common.i18n.I18nTest.shouldProvideIdempotentInitialization(I18nTest.java:201)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.junit.internal.runners.TestMethod.invoke(TestMethod.java:59)
at org.junit.internal.runners.MethodRoadie.runTestMethod(MethodRoadie.java:98)
at org.junit.internal.runners.MethodRoadie$2.run(MethodRoadie.java:79)
at org.junit.internal.runners.MethodRoadie.runBeforesThenTestThenAfters(MethodRoadie.java:87)
at org.junit.internal.runners.MethodRoadie.runTest(MethodRoadie.java:77)
at org.junit.internal.runners.MethodRoadie.run(MethodRoadie.java:42)
at org.junit.internal.runners.JUnit4ClassRunner.invokeTestMethod(JUnit4ClassRunner.java:88)
at org.junit.internal.runners.JUnit4ClassRunner.runMethods(JUnit4ClassRunner.java:51)
at org.junit.internal.runners.JUnit4ClassRunner$1.run(JUnit4ClassRunner.java:44)
at org.junit.internal.runners.ClassRoadie.runUnprotected(ClassRoadie.java:27)
at org.junit.internal.runners.ClassRoadie.runProtected(ClassRoadie.java:37)
at org.junit.internal.runners.JUnit4ClassRunner.run(JUnit4ClassRunner.java:42)
at org.apache.maven.surefire.junit4.JUnit4TestSet.execute(JUnit4TestSet.java:62)
at org.apache.maven.surefire.suite.AbstractDirectoryTestSuite.executeTestSet(AbstractDirectoryTestSuite.java:140)
at org.apache.maven.surefire.suite.AbstractDirectoryTestSuite.execute(AbstractDirectoryTestSuite.java:127)
at org.apache.maven.surefire.Surefire.run(Surefire.java:177)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.apache.maven.surefire.booter.SurefireBooter.runSuitesInProcess(SurefireBooter.java:338)
at org.apache.maven.surefire.booter.SurefireBooter.main(SurefireBooter.java:997)