Revision 392556

Fix for problem reported by: Christopher G. Stach II

We're using Resin and trying to use 4.0-RC2.  It just so happens that
Resin makes this call in ConnectionPool.init(ManagedConnectionFactory):

ManagedConnection mConn = mcf.createManagedConnection(subject, null);

So, eventually that null info gets dereferenced and BOOM!

com.caucho.server.webapp.Application.start java.lang.NullPointerException
       at org.apache.activemq.ra.ActiveMQResourceAdapter.createConnectionFactory(ActiveMQResourceAdapter.java:156)
       at org.apache.activemq.ra.ActiveMQResourceAdapter.makeConnection(ActiveMQResourceAdapter.java:100)
       at org.apache.activemq.ra.ActiveMQManagedConnectionFactory.createManagedConnection(ActiveMQManagedConnectionFactory.java:103)
       at com.caucho.jca.ConnectionPool.init(ConnectionPool.java:462)