ActiveObjectsImportExportException thrown during export when using MS JDBC connection

2013-04-10 09:22:53,607 QuartzWorker-0 INFO ServiceRunner    Backup Service [jira.bc.dataimport.DefaultExportService] Data export completed in 9517ms. Wrote 155300 entities to export in memory.
2013-04-10 09:22:53,607 QuartzWorker-0 INFO ServiceRunner    Backup Service [jira.bc.dataimport.DefaultExportService] Attempting to save the Active Objects Backup
2013-04-10 09:22:54,186 QuartzWorker-0 ERROR ServiceRunner    Backup Service [jira.bc.dataimport.DefaultExportService] Error during Active Objects Backup
com.atlassian.activeobjects.spi.ActiveObjectsImportExportException: There was an error during import/export with plugin Tempo Plugin(is.origo.jira.tempo-plugin) #7.5.3:Cannot encode value for unsupported column type: "ntext" (-16) of column AO_86ED1B_TIMEPLAN.DESCRIPTION
	at com.atlassian.activeobjects.backup.ImportExportErrorServiceImpl.newImportExportException(ImportExportErrorServiceImpl.java:24)
	at com.atlassian.dbexporter.exporter.DataExporter.exportRow(DataExporter.java:164)
	at com.atlassian.dbexporter.exporter.DataExporter.exportTable(DataExporter.java:92)
	at com.atlassian.dbexporter.exporter.DataExporter.access$100(DataExporter.java:28)
	at com.atlassian.dbexporter.exporter.DataExporter$1.call(DataExporter.java:50)
	at com.atlassian.dbexporter.exporter.DataExporter$1.call(DataExporter.java:45)
	at com.atlassian.dbexporter.jdbc.JdbcUtils.withConnection(JdbcUtils.java:30)
	at com.atlassian.dbexporter.exporter.DataExporter.export(DataExporter.java:44)
	at com.atlassian.dbexporter.DbExporter.exportData(DbExporter.java:53)
	at com.atlassian.activeobjects.backup.ActiveObjectsBackup.save(ActiveObjectsBackup.java:112)
	at com.atlassian.jira.bc.dataimport.DefaultExportService.exportActiveObjects(DefaultExportService.java:198)
	at com.atlassian.jira.bc.dataimport.DefaultExportService.export(DefaultExportService.java:80)
	at com.atlassian.jira.bc.dataimport.DefaultExportService.export(DefaultExportService.java:59)
	at com.atlassian.jira.service.services.export.ExportService.performBackup(ExportService.java:145)
	at com.atlassian.jira.service.services.export.ExportService.run(ExportService.java:130)
	at com.atlassian.jira.service.JiraServiceContainerImpl.run(JiraServiceContainerImpl.java:61)
	at com.atlassian.jira.service.ServiceRunner.execute(ServiceRunner.java:47)
	at org.quartz.core.JobRunShell.run(JobRunShell.java:195)
	at com.atlassian.multitenant.quartz.MultiTenantThreadPool$MultiTenantRunnable.run(MultiTenantThreadPool.java:72)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:520)
2013-04-10 09:22:54,186 QuartzWorker-0 ERROR ServiceRunner    Backup Service [service.services.export.ExportService] An exception while running the export service "Backup Service": There was a problem backing up data for the Tempo Plugin plugin.
com.atlassian.core.AtlassianCoreException: There was a problem backing up data for the Tempo Plugin plugin.
	at com.atlassian.jira.service.services.export.ExportService.performBackup(ExportService.java:148)
	at com.atlassian.jira.service.services.export.ExportService.run(ExportService.java:130)
	at com.atlassian.jira.service.JiraServiceContainerImpl.run(JiraServiceContainerImpl.java:61)
	at com.atlassian.jira.service.ServiceRunner.execute(ServiceRunner.java:47)
	at org.quartz.core.JobRunShell.run(JobRunShell.java:195)
	at com.atlassian.multitenant.quartz.MultiTenantThreadPool$MultiTenantRunnable.run(MultiTenantThreadPool.java:72)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:520)
2013-04-10 09:22:54,248 QuartzWorker-0 WARN ServiceRunner    Backup Service [service.services.export.ExportService] The corrupted backup file 'C:\Program Files (x86)\Atlassian\Application Data\JIRA\export\2013-Apr-10--0922.zip' was copied to 'C:\Program Files (x86)\Atlassian\Application Data\JIRA\export\corrupted\2013-Apr-10--0922.zip' but could not be deleted.
2013-04-10 09:22:54,248 QuartzWorker-0 ERROR ServiceRunner    Backup Service [atlassian.jira.service.ServiceRunner] An error occured while trying to run service 'Backup Service'. null
java.lang.NullPointerException
	at com.atlassian.jira.service.services.export.ExportService.writeFailureReasonFile(ExportService.java:256)
	at com.atlassian.jira.service.services.export.ExportService.moveBackupAside(ExportService.java:196)
	at com.atlassian.jira.service.services.export.ExportService.run(ExportService.java:136)
	at com.atlassian.jira.service.JiraServiceContainerImpl.run(JiraServiceContainerImpl.java:61)
	at com.atlassian.jira.service.ServiceRunner.execute(ServiceRunner.java:47)
	at org.quartz.core.JobRunShell.run(JobRunShell.java:195)
	at com.atlassian.multitenant.quartz.MultiTenantThreadPool$MultiTenantRunnable.run(MultiTenantThreadPool.java:72)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:520)