Could not initialize proxy - the owning Session was closed

This is occasionally killing the DR5 on confluence.atlassian.com:

[ERROR] Wed Nov 24 07:44:12 CST 2004
[net.sf.hibernate.proxy.LazyInitializer] Exception initializing proxy
Throwable:
net.sf.hibernate.HibernateException: Could not initialize proxy - the
owning Session was closed
at
net.sf.hibernate.proxy.LazyInitializer.initialize(LazyInitializer.java:47)
at
net.sf.hibernate.proxy.LazyInitializer.initializeWrapExceptions(LazyInitializer.java:60)

at
net.sf.hibernate.proxy.LazyInitializer.getImplementation(LazyInitializer.java:164)

at
net.sf.hibernate.proxy.CGLIBLazyInitializer.intercept(CGLIBLazyInitializer.java:108)

at
com.atlassian.confluence.spaces.Space$$EnhancerByCGLIB$$6c6ddc66.getKey()
at
com.atlassian.confluence.core.SpaceContentEntityObject.hashCode(SpaceContentEntityObject.java:36)

at net.sf.hibernate.engine.TypedValue.hashCode(TypedValue.java:45)
at java.util.HashMap$Entry.hashCode(HashMap.java:707)
at java.util.AbstractMap.hashCode(AbstractMap.java:556)
at net.sf.hibernate.cache.QueryKey.hashCode(QueryKey.java:63)
at java.util.HashMap.hash(HashMap.java:261)
at java.util.HashMap.removeEntryForKey(HashMap.java:538)
at java.util.LinkedHashMap.addEntry(LinkedHashMap.java:396)
at java.util.HashMap.put(HashMap.java:392)
at net.sf.ehcache.store.MemoryStore.put(MemoryStore.java:177)
at net.sf.ehcache.Cache.put(Cache.java:318)
at net.sf.ehcache.hibernate.Plugin.put(Plugin.java:146)
at
net.sf.hibernate.cache.StandardQueryCache.put(StandardQueryCache.java:59)
at net.sf.hibernate.loader.Loader.list(Loader.java:1019)
[ERROR] Wed Nov 24 07:44:12 CST 2004
[com.atlassian.confluence.util.XWorkTransactionInterceptor] Invoking
rollback for transaction on action '/pages/viewpage.action
(ViewPageAction.execute())' due to throwable:
net.sf.hibernate.LazyInitializationException: Exception initializing proxy:
com.atlassian.confluence.spaces.Space#1
Throwable:
net.sf.hibernate.LazyInitializationException: Exception initializing proxy:
com.atlassian.confluence.spaces.Space#1
at
net.sf.hibernate.proxy.LazyInitializer.initializeWrapExceptions(LazyInitializer.java:64)

at
net.sf.hibernate.proxy.LazyInitializer.getImplementation(LazyInitializer.java:164)

at
net.sf.hibernate.proxy.CGLIBLazyInitializer.intercept(CGLIBLazyInitializer.java:108)

at
com.atlassian.confluence.spaces.Space$$EnhancerByCGLIB$$6c6ddc66.getKey()
at
com.atlassian.confluence.core.SpaceContentEntityObject.hashCode(SpaceContentEntityObject.java:36)

at net.sf.hibernate.engine.TypedValue.hashCode(TypedValue.java:45)
at java.util.HashMap$Entry.hashCode(HashMap.java:707)
at java.util.AbstractMap.hashCode(AbstractMap.java:556)
at net.sf.hibernate.cache.QueryKey.hashCode(QueryKey.java:63)
at java.util.HashMap.hash(HashMap.java:261)
at java.util.HashMap.removeEntryForKey(HashMap.java:538)
at java.util.LinkedHashMap.addEntry(LinkedHashMap.java:396)
at java.util.HashMap.put(HashMap.java:392)
at net.sf.ehcache.store.MemoryStore.put(MemoryStore.java:177)
at net.sf.ehcache.Cache.put(Cache.java:318)
at net.sf.ehcache.hibernate.Plugin.put(Plugin.java:146)
at
net.sf.hibernate.cache.StandardQueryCache.put(StandardQueryCache.java:59)
at net.sf.hibernate.loader.Loader.list(Loader.java:1019)
at net.sf.hibernate.hql.QueryTranslator.list(QueryTranslator.java:854)
[ERROR] Wed Nov 24 07:44:12 CST 2004
[com.opensymphony.webwork.dispatcher.ServletDispatcher] Could not execute
action
Throwable:
net.sf.hibernate.LazyInitializationException: Exception initializing proxy:
com.atlassian.confluence.spaces.Space#1
at
net.sf.hibernate.proxy.LazyInitializer.initializeWrapExceptions(LazyInitializer.java:64)

at
net.sf.hibernate.proxy.LazyInitializer.getImplementation(LazyInitializer.java:164)

at
net.sf.hibernate.proxy.CGLIBLazyInitializer.intercept(CGLIBLazyInitializer.java:108)

at
com.atlassian.confluence.spaces.Space$$EnhancerByCGLIB$$6c6ddc66.getKey()
at
com.atlassian.confluence.core.SpaceContentEntityObject.hashCode(SpaceContentEntityObject.java:36)

at net.sf.hibernate.engine.TypedValue.hashCode(TypedValue.java:45)
at java.util.HashMap$Entry.hashCode(HashMap.java:707)
at java.util.AbstractMap.hashCode(AbstractMap.java:556)
at net.sf.hibernate.cache.QueryKey.hashCode(QueryKey.java:63)
at java.util.HashMap.hash(HashMap.java:261)
at java.util.HashMap.removeEntryForKey(HashMap.java:538)
at java.util.LinkedHashMap.addEntry(LinkedHashMap.java:396)
at java.util.HashMap.put(HashMap.java:392)
at net.sf.ehcache.store.MemoryStore.put(MemoryStore.java:177)
at net.sf.ehcache.Cache.put(Cache.java:318)
at net.sf.ehcache.hibernate.Plugin.put(Plugin.java:146)
at
net.sf.hibernate.cache.StandardQueryCache.put(StandardQueryCache.java:59)
at net.sf.hibernate.loader.Loader.list(Loader.java:1019)
at net.sf.hibernate.hql.QueryTranslator.list(QueryTranslator.java:854)