XML backup restore fails with unique index error if db collate is change from a case sensitive one to a insensitive one

2011-03-04 09:14:46,710 http-8080-1 ERROR anonymous 554x40x1 1rdh6sz 0:0:0:0:0:0:0:1 /secure/SetupImport.jspa [jira.action.admin.DataImport] Error importing data: 
org.apache.commons.lang.exception.NestableException: com.atlassian.jira.exception.DataAccessException: org.ofbiz.core.entity.GenericEntityException: while inserting: 
[GenericEntity:UserHistoryItem][id,11887][username,showlett][entityId,10613][lastViewed,1286786159742][type,Issue] (SQL Exception while executing the following:INSERT 
INTO userhistoryitem (ID, entitytype, entityid, USERNAME, lastviewed, data) VALUES (?, ?, ?, ?, ?, ?) (Duplicate entry 'Issue-showlett-10613' for key 
'uh_type_user_entity'))
org.apache.commons.lang.exception.NestableException: com.atlassian.jira.exception.DataAccessException: org.ofbiz.core.entity.GenericEntityException: while inserting: 
[GenericEntity:UserHistoryItem][id,11887][username,showlett][entityId,10613][lastViewed,1286786159742][type,Issue] (SQL Exception while executing the following:INSERT 
INTO userhistoryitem (ID, entitytype, entityid, USERNAME, lastviewed, data) VALUES (?, ?, ?, ?, ?, ?) (Duplicate entry 'Issue-showlett-10613' for key 'uh_type_user_entity'))
	at com.atlassian.jira.action.admin.OfbizImportHandler.startElement(OfbizImportHandler.java:122)
	at org.apache.xerces.parsers.AbstractSAXParser.startElement(Unknown Source)
	at org.apache.xerces.parsers.AbstractXMLDocumentParser.emptyElement(Unknown Source)
...
Caused by: org.apache.commons.lang.exception.NestableException: com.atlassian.jira.exception.DataAccessException: org.ofbiz.core.entity.GenericEntityException: while 
inserting: [GenericEntity:UserHistoryItem][id,11887][username,showlett][entityId,10613][lastViewed,1286786159742][type,Issue] (SQL Exception while executing the 
following:INSERT INTO userhistoryitem (ID, entitytype, entityid, USERNAME, lastviewed, data) VALUES (?, ?, ?, ?, ?, ?) (Duplicate entry 'Issue-showlett-10613' for key 
'uh_type_user_entity'))
	... 151 more
Caused by: com.atlassian.jira.exception.DataAccessException: org.ofbiz.core.entity.GenericEntityException: while inserting: [GenericEntity:UserHistoryItem][id,11887]
[username,showlett][entityId,10613][lastViewed,1286786159742][type,Issue] (SQL Exception while executing the following:INSERT INTO userhistoryitem (ID, entitytype, 
entityid, USERNAME, lastviewed, data) VALUES (?, ?, ?, ?, ?, ?) (Duplicate entry 'Issue-showlett-10613' for key 'uh_type_user_entity'))
	at com.atlassian.jira.action.admin.OfbizImportHandler$1.run(OfbizImportHandler.java:482)
	at com.atlassian.jira.util.concurrent.BoundedExecutor$1.run(BoundedExecutor.java:43)
	at com.atlassian.multitenant.impl.DefaultMultiTenantManager.runForTenant(DefaultMultiTenantManager.java:61)
	at com.atlassian.multitenant.juc.MultiTenantExecutors$WrappedRunnable.run(MultiTenantExecutors.java:160)
	at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
	... 1 more
Caused by: org.ofbiz.core.entity.GenericEntityException: while inserting: [GenericEntity:UserHistoryItem][id,11887][username,showlett][entityId,10613]
[lastViewed,1286786159742][type,Issue] (SQL Exception while executing the following:INSERT INTO userhistoryitem (ID, entitytype, entityid, USERNAME, lastviewed, data) 
VALUES (?, ?, ?, ?, ?, ?) (Duplicate entry 'Issue-showlett-10613' for key 'uh_type_user_entity'))
	at org.ofbiz.core.entity.GenericDAO.singleInsert(GenericDAO.java:156)
	at org.ofbiz.core.entity.GenericDAO.insert(GenericDAO.java:121)
	at org.ofbiz.core.entity.GenericHelperDAO.create(GenericHelperDAO.java:63)
	at org.ofbiz.core.entity.GenericDelegator.create(GenericDelegator.java:489)
	at org.ofbiz.core.entity.GenericDelegator.create(GenericDelegator.java:469)
	at org.ofbiz.core.entity.GenericValue.create(GenericValue.java:77)
	at com.atlassian.jira.action.admin.OfbizImportHandler$1.run(OfbizImportHandler.java:471)