I'm using the PooledInvoker and client certificate authentication to EJBs with mixed success. Periodically method calls fail because there is no principal/credential passed into the login modules. I was able to duplicate the problem with org.jboss.test.pooled.test.SSLSocketsUnitTestCase from the testsuite. However, the behavior is not consistent. If you loop through the call to echoCaller 1,000 times it fails most of the time. I'm running JBoss-4.0.4.CR2 ejb3 installation. I'm using Sun's JDK 1.5.0_06 running on Windows XP Pro. If you can't duplicate the problem and would like to see my logs let me know.