java.util.ConcurrentModificationException: null
at java.util.LinkedHashMap$LinkedHashIterator.nextEntry(LinkedHashMap.java:373) ~[na:1.6.0_16]
at java.util.LinkedHashMap$KeyIterator.next(LinkedHashMap.java:384) ~[na:1.6.0_16]
at org.apache.jackrabbit.core.version.InternalVersionHistoryImpl.fixLegacy(InternalVersionHistoryImpl.java:170) ~[jackrabbit-core-2.4.3.jar:2.4.3]
at org.apache.jackrabbit.core.version.InternalVersionHistoryImpl.<init>(InternalVersionHistoryImpl.java:114) ~[jackrabbit-core-2.4.3.jar:2.4.3]
at org.apache.jackrabbit.core.version.InternalVersionManagerBase.createInternalVersionItem(InternalVersionManagerBase.java:865) ~[jackrabbit-core-2.4.3.jar:2.4.3]
at org.apache.jackrabbit.core.version.InternalVersionManagerImpl.getItem(InternalVersionManagerImpl.java:335) ~[jackrabbit-core-2.4.3.jar:2.4.3]
at org.apache.jackrabbit.core.version.InternalXAVersionManager.getItem(InternalXAVersionManager.java:432) ~[jackrabbit-core-2.4.3.jar:2.4.3]
at org.apache.jackrabbit.core.version.InternalVersionManagerBase.getVersionHistory(InternalVersionManagerBase.java:138) ~[jackrabbit-core-2.4.3.jar:2.4.3]
at org.apache.jackrabbit.core.version.InternalXAVersionManager.getVersionHistory(InternalXAVersionManager.java:56) ~[jackrabbit-core-2.4.3.jar:2.4.3]
at org.apache.jackrabbit.core.version.VersionManagerImplBase.getVersionHistory(VersionManagerImplBase.java:357) ~[jackrabbit-core-2.4.3.jar:2.4.3]
at org.apache.jackrabbit.core.VersionManagerImpl.access$700(VersionManagerImpl.java:73) ~[jackrabbit-core-2.4.3.jar:2.4.3]
at org.apache.jackrabbit.core.VersionManagerImpl$4.perform(VersionManagerImpl.java:184) ~[jackrabbit-core-2.4.3.jar:2.4.3]
at org.apache.jackrabbit.core.VersionManagerImpl$4.perform(VersionManagerImpl.java:180) ~[jackrabbit-core-2.4.3.jar:2.4.3]
at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:216) ~[jackrabbit-core-2.4.3.jar:2.4.3]
at org.apache.jackrabbit.core.VersionManagerImpl.perform(VersionManagerImpl.java:96) ~[jackrabbit-core-2.4.3.jar:2.4.3]
at org.apache.jackrabbit.core.VersionManagerImpl.getVersionHistory(VersionManagerImpl.java:180) ~[jackrabbit-core-2.4.3.jar:2.4.3]