I get 2 at a time that look like this:

Product name: Zimbra Desktop
Product version: 1.0
Build ID: 1593
Release type: R
OS Platform: Mac OS X i386 10.4.11
Time of event: 2009-10-27 11:05:59
Error type: mail.NO_SUCH_BLOB
Item ID: 830
Error summary: Append message failed

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Affected data - PLEASE REMOVE ANY SENSITIVE INFORMATION (size=21):
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Local folder: /Inbox


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Failure details - PLEASE REMOVE ANY SENSITIVE INFORMATION
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com.zimbra.cs.mailbox.MailServiceException: No such blob: mailbox=4, item=830, change=509
ExceptionId:mid=4:1256666759304:3c2b066f931316b1
Code:mail.NO_SUCH_BLOB
at com.zimbra.cs.mailbox.MailServiceException.NO_SUCH _BLOB(MailServiceException.java:264)
at com.zimbra.cs.mailbox.MailItem.getBlob(MailItem.ja va:854)
at com.zimbra.cs.mailbox.MessageCache.fetchFromStore( MessageCache.java:290)
at com.zimbra.cs.mailbox.MessageCache.getMimeMessage( MessageCache.java:233)
at com.zimbra.cs.mailbox.Message.getMimeMessage(Messa ge.java:298)
at com.zimbra.cs.datasource.ImapFolderSync.appendMess age(ImapFolderSync.java:572)
at com.zimbra.cs.datasource.ImapFolderSync.appendMess ages(ImapFolderSync.java:561)
at com.zimbra.cs.datasource.ImapFolderSync.appendNewM essages(ImapFolderSync.java:531)
at com.zimbra.cs.datasource.ImapFolderSync.finishSync (ImapFolderSync.java:406)
at com.zimbra.cs.datasource.ImapSync.finishSync(ImapS ync.java:277)
at com.zimbra.cs.datasource.ImapSync.syncFolders(Imap Sync.java:196)
at com.zimbra.cs.datasource.ImapSync.importData(ImapS ync.java:152)
at com.zimbra.cs.offline.OfflineImport.importData(Off lineImport.java:88)
at com.zimbra.cs.datasource.DataSourceManager.importD ata(DataSourceManager.java:154)
at com.zimbra.cs.mailbox.LocalMailbox.importData(Loca lMailbox.java:417)
at com.zimbra.cs.mailbox.LocalMailbox.syncAllLocalDat aSources(LocalMailbox.java:389)
at com.zimbra.cs.mailbox.LocalMailbox.sync(LocalMailb ox.java:431)
at com.zimbra.cs.mailbox.LocalMailbox.syncOnTimer(Loc alMailbox.java:361)
at com.zimbra.cs.mailbox.DesktopMailbox$1.run(Desktop Mailbox.java:437)
at java.util.TimerThread.mainLoop(Timer.java:512)
at java.util.TimerThread.run(Timer.java:462)

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