Class Cast Exception being thrown when error encountered during mail queue flushing

2009-03-13 03:00:00,011 ERROR [DefaultQuartzScheduler_Worker-0] [org.quartz.core.JobRunShell] run Job DEFAULT.clearOldMailErrorsJob threw an unhandled Exception: 
java.lang.ClassCastException: com.atlassian.confluence.mail.template.ConfluenceMailQueueItem cannot be cast to com.atlassian.confluence.mail.template.MailNotificationQueueItem
	at com.atlassian.confluence.mail.jobs.ClearOldMailErrors.doExecute(ClearOldMailErrors.java:33)
	at com.atlassian.quartz.jobs.AbstractJob.executeInternal(AbstractJob.java:87)
	at org.springframework.scheduling.quartz.QuartzJobBean.execute(QuartzJobBean.java:86)
	at com.atlassian.confluence.setup.quartz.DelegatingClusterAwareQuartzJobBean.executeJob(DelegatingClusterAwareQuartzJobBean.java:16)
	at com.atlassian.confluence.setup.quartz.AbstractClusterAwareQuartzJobBean.surroundJobExecutionWithLogging(AbstractClusterAwareQuartzJobBean.java:64)
	at com.atlassian.confluence.setup.quartz.AbstractClusterAwareQuartzJobBean.executeInternal(AbstractClusterAwareQuartzJobBean.java:47)
	at org.springframework.scheduling.quartz.QuartzJobBean.execute(QuartzJobBean.java:86)
	at org.quartz.core.JobRunShell.run(JobRunShell.java:203)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:520)
2009-03-13 03:00:00,041 ERROR [DefaultQuartzScheduler_Worker-0] [org.quartz.core.ErrorLogger] schedulerError Job (DEFAULT.clearOldMailErrorsJob threw an exception.
org.quartz.SchedulerException: Job threw an unhandled exception. [See nested exception: java.lang.ClassCastException: com.atlassian.confluence.mail.template.ConfluenceMailQueueItem cannot be cast to com.atlassian.confluence.mail.template.MailNotificationQueueItem]
	at org.quartz.core.JobRunShell.run(JobRunShell.java:214)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:520)
* Nested Exception (Underlying Cause) ---------------
java.lang.ClassCastException: com.atlassian.confluence.mail.template.ConfluenceMailQueueItem cannot be cast to com.atlassian.confluence.mail.template.MailNotificationQueueItem
	at com.atlassian.confluence.mail.jobs.ClearOldMailErrors.doExecute(ClearOldMailErrors.java:33)
	at com.atlassian.quartz.jobs.AbstractJob.executeInternal(AbstractJob.java:87)
	at org.springframework.scheduling.quartz.QuartzJobBean.execute(QuartzJobBean.java:86)
	at com.atlassian.confluence.setup.quartz.DelegatingClusterAwareQuartzJobBean.executeJob(DelegatingClusterAwareQuartzJobBean.java:16)
	at com.atlassian.confluence.setup.quartz.AbstractClusterAwareQuartzJobBean.surroundJobExecutionWithLogging(AbstractClusterAwareQuartzJobBean.java:64)
	at com.atlassian.confluence.setup.quartz.AbstractClusterAwareQuartzJobBean.executeInternal(AbstractClusterAwareQuartzJobBean.java:47)
	at org.springframework.scheduling.quartz.QuartzJobBean.execute(QuartzJobBean.java:86)
	at org.quartz.core.JobRunShell.run(JobRunShell.java:203)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:520)