Legacy portlet to gadget upgrade task (438) can't deal with duplicate propertyset keys

2009-11-05 14:22:39,444 http-8090-Processor3 ERROR anonymous 51649x4x1 1yhx9mz /secure/SetupImport.jspa [atlassian.jira.upgrade.UpgradeManagerImpl] Exception thrown during upgrade: Property not found
com.opensymphony.module.propertyset.PropertyImplementationException: Property not found
	at com.opensymphony.module.propertyset.ofbiz.OFBizPropertySet.getType(OFBizPropertySet.java:110)
	at com.opensymphony.module.propertyset.ofbiz.OFBizPropertySet.remove(OFBizPropertySet.java:140)
	at com.atlassian.jira.upgrade.tasks.UpgradeTask_Build438.removePropertySet(UpgradeTask_Build438.java:160)
	at com.atlassian.jira.upgrade.tasks.UpgradeTask_Build438.doUpgrade(UpgradeTask_Build438.java:117)
	at com.atlassian.jira.upgrade.UpgradeManagerImpl.doUpgradeTaskSucess(UpgradeManagerImpl.java:508)
	at com.atlassian.jira.upgrade.UpgradeManagerImpl.runUpgradeTasks(UpgradeManagerImpl.java:419)
	at com.atlassian.jira.upgrade.UpgradeManagerImpl.doUpgrade(UpgradeManagerImpl.java:356)
	at com.atlassian.jira.upgrade.UpgradeManagerImpl.doUpgradeIfNeeded(UpgradeManagerImpl.java:307)
	at com.atlassian.jira.upgrade.UpgradeManagerImpl.doUpgradeIfNeededAndAllowed(UpgradeManagerImpl.java:246)
	at com.atlassian.jira.action.admin.DataImport.doExecute(DataImport.java:248)
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