There is some vagaries associated with this test when run as a collection, part of the target "tests-security-basic-unit" against a jboss instance in the all config.
Here the testcase consistently throws failures/errors.

Now if this testcase is run standalone as

$>ant -Dtest=org.jboss.test.timer.test.SecureTimerUnitTestCase one-test

The first time there are a couple of errors but when this test is again run, the testcase passes.

From the log files, I see:
=====================================================================================================
(1:31:47 PM) anil_aol: Caused by: java.lang.SecurityException: Invalid authentication attempt, principal=null
at org.jboss.resource.connectionmanager.BaseConnectionManager2.getSubject(BaseConnectionManager2.java:587)
at org.jboss.resource.connectionmanager.BaseConnectionManager2.allocateConnection(BaseConnectionManager2.java:393)
at org.jboss.resource.connectionmanager.BaseConnectionManager2$ConnectionManagerProxy.allocateConnection(BaseConnectionManager2.java:838)
at org.jboss.resource.adapter.jdbc.WrapperDataSource.getConnection(WrapperDataSource.java:88)
at org.jboss.ejb.txtimer.GeneralPurposeDatabasePersistencePlugin.selectTimers(GeneralPurposeDatabasePersistencePlugin.java:207)^M
at org.jboss.ejb.txtimer.DatabasePersistencePolicy.listTimerHandles(DatabasePersistencePolicy.java:164)

......

• Nested Exception (Underlying Cause) ---------------
  java.sql.SQLException: Could not retrieve datasource via JNDI url 'java:DefaultDS' java.lang.SecurityException: Invalid authentication attempt, principal=null
  at org.quartz.utils.JNDIConnectionProvider.getConnection(JNDIConnectionProvider.java:166)
  at org.quartz.utils.DBConnectionManager.getConnection(DBConnectionManager.java:111)
  at org.quartz.impl.jdbcjobstore.JobStoreCMT.getNonManagedTXConnection(JobStoreCMT.java:1431)
  at org.quartz.impl.jdbcjobstore.JobStoreCMT.doRecoverMisfires(JobStoreCMT.java:1335)
  at org.quartz.impl.jdbcjobstore.JobStoreSupport$MisfireHandler.manage(JobStoreSupport.java:2449)
  =============================================================================================

Please verify that this is not a Quart integration layer issue.