[rules-users] NullPointerException in SessionConfiguration

Any advice on this NPE? (March 20th snapshot of 5.00) It occurs when a second thread attempts to create a session using a static KnowledgeBase. java.lang.NullPointerException at org.drools.SessionConfiguration.initProcessInstanceManagerFactory (SessionConfiguration.java:260) at org.drools.SessionConfiguration.getProcessInstanceManagerFactory (SessionConfiguration.java:249) at org.drools.common.AbstractWorkingMemory.<init>(AbstractWorkingMemory.java:295) at org.drools.common.AbstractWorkingMemory.<init>(AbstractWorkingMemory.java:239) at org.drools.reteoo.ReteooWorkingMemory.<init>(ReteooWorkingMemory.java:85) at org.drools.reteoo.ReteooStatefulSession.<init>(ReteooStatefulSession.java:67) at org.drools.reteoo.ReteooRuleBase.newStatefulSession(ReteooRuleBase.java:325) at org.drools.reteoo.ReteooRuleBase.newStatefulSession(ReteooRuleBase.java:310) at org.drools.impl.KnowledgeBaseImpl.newStatefulKnowledgeSession (KnowledgeBaseImpl.java:151) at org.drools.impl.KnowledgeBaseImpl.newStatefulKnowledgeSession (KnowledgeBaseImpl.java:134)