Enabling Caching for Hibernate Repository causes net.sf.hibernate.LazyInitializationException error

<hibernate name="Hibernate Repository" key="hibernateRepository"  description="Hibernate Repository" cache="true" />

 Cause:
net.sf.hibernate.LazyInitializationException: Failed to lazily initialize a collection - no session or session was closed
at net.sf.hibernate.collection.PersistentCollection.initialize(PersistentCollection.java:209)

Stack Trace: [hide]

net.sf.hibernate.LazyInitializationException: Failed to lazily initialize a collection - no session or session was closed
at net.sf.hibernate.collection.PersistentCollection.initialize(PersistentCollection.java:209)
at net.sf.hibernate.collection.PersistentCollection.read(PersistentCollection.java:71)
at net.sf.hibernate.collection.Set.contains(Set.java:122)
at com.atlassian.user.impl.hibernate.HibernateGroupManager.hasExternalMembership(HibernateGroupManager.java:461)
at com.atlassian.user.impl.hibernate.HibernateGroupManager.hasMembership(HibernateGroupManager.java:437)
at com.atlassian.user.impl.cache.CachingGroupManager.hasMembership(CachingGroupManager.java:149)
at com.atlassian.user.impl.delegation.DelegatingGroupManagerTemplate.hasMembership(DelegatingGroupManagerTemplate.java:189)