JUnit test failures that occur in threads other than the main thread are not propagated to the test itself.

E.g. when looking at the problem mentioned in http://forums.opensymphony.com/thread.jspa?threadID=6334&tstart=0 the failures below are logged. However the tests themselves succeed!

junit.framework.AssertionFailedError: Thread should have blocked until a new cache entry was ready
at junit.framework.Assert.fail(Assert.java:47)
at com.opensymphony.oscache.base.TestConcurrency$GetEntry.run(TestConcurrency.java:301)
at java.lang.Thread.run(Thread.java:534)
junit.framework.AssertionFailedError: Thread should have blocked until a new cache entry was ready
at junit.framework.Assert.fail(Assert.java:47)
at com.opensymphony.oscache.base.TestConcurrency$GetEntry.run(TestConcurrency.java:301)
at java.lang.Thread.run(Thread.java:534)

Links:
http://today.java.net/pub/a/today/2003/08/06/multithreadedTests.html
http://www.clarkware.com/software/JUnitPerf.html

Taken from http://forums.opensymphony.com/thread.jspa?threadID=6955&tstart=0