TypeResolver NPE (5.4.2.Final)

I am experiencing an intermittent failure (NullPointerException) from org.hibernate.type.TypeResolver.heuristicType(…). Here is an abstract of the trace:

java.lang.NullPointerException
at org.hibernate.type.TypeResolver.heuristicType(TypeResolver.java:123)
at org.hibernate.mapping.SimpleValue.getType(SimpleValue.java:471)
at org.hibernate.mapping.Property.getType(Property.java:69)
at com.fbc.util.hibernate.HibernateUtil.getForeignTables(HibernateUtil.java:1380)

It looks like the TypeConfiguration$Scope.getServiceRegistry() call is returning null. I not yet created a reliable test case to consistently reproduce the issue, but just wondering if anyone has come across similar?