I've recently upgraded to Beta 3 and am getting the following worrying messages in my log file:

1) Possibly Corrupt Index:
I've seen this, or similar in the log file several times. It always reports zero indexing operations failed.
Code:
2008-08-05 06:45:43,500 DEBUG [sync-timer-xxx@xxx.net] [mid=3;] offline - starting delta sync [token 141958]
2008-08-05 06:45:43,515 DEBUG [sync-timer-xxx@xxx.net] [mid=3;] offline - delta: updated message (65805): USAID - brainstorm proposal ideas
2008-08-05 06:45:45,296 WARN  [sync-timer-xxx@xxx.net] [mid=3;] index - Possibly corrupt index: 0 indexing operations failed in mailbox transaction.
2008-08-05 06:45:45,312 DEBUG [sync-timer-xxx@xxx.net] [mid=3;] offline - initial: created appointment 65807: USAID - brainstorm proposal ideas
.......>8 CUT for BREVITY, "several creates" 8<.............
2008-08-05 06:46:18,593 DEBUG [sync-timer-xxx@xxx.net] [mid=3;] offline - ending delta sync [token 141973]
The first time it appeared in the log files was this, slightly different, message:
Code:
2008-08-02 09:54:45,609 DEBUG [sync-timer-xxx@xxx.net] [mid=3;] offline - starting delta sync [token 141404]
2008-08-02 09:54:45,609 DEBUG [sync-timer-xxx@xxx.net] [mid=3;] offline - delta: updated message (65644): Indonesia Planning Meeting
2008-08-02 09:54:45,625 DEBUG [sync-timer-xxx@xxx.net] [mid=3;] offline - delta: updated message (65646): Your daily e-mail from the BBC
2008-08-02 09:54:45,718 DEBUG [sync-timer-xxx@xxx.net] [mid=3;] offline - ending delta sync [token 141406]
2008-08-02 09:55:25,781 WARN  [btpool0-37] [name=xxx@xxx.net;mid=3;ip=127.0.0.1;ua=ZimbraWebClient - PRISM (Win)/0.0;] index - Possibly corrupt index: 0 indexing operations failed in mailbox transaction.
2008-08-02 09:55:31,437 DEBUG [sync-timer-xxx@xxx.net] [mid=3;] offline - push: sent pending mail (1073746545): Accept: Indonesia Planning Meeting
2008-08-02 09:55:31,515 DEBUG [sync-timer-xxx@xxx.net] [mid=3;] offline - push: deleted pending draft (1073746545)
Corrupt indices sound worrying. Should I do something?

2. Sync failure related to "zimbraPrefCalendarReminderFlashTitle: attribute type undefined".
This message has appeared every fifteen minutes in the log files since upgrading:
Code:
2008-08-02 09:52:28,171 INFO  [sync-timer-dir] [] offline - dsync: remote server version: 5.0.5_GA_2201.RHEL4_64 20080417001606 20080417-0016 NETWORK
2008-08-02 09:52:29,796 DEBUG [sync-timer-dir] [] offline - dsync: synchronized account: xxx@xxx.net
2008-08-02 09:52:29,843 DEBUG [sync-timer-dir] [] offline - dsync: updated identity: xxx@xxx.net/John Kate Marsden
2008-08-02 09:52:29,843 DEBUG [sync-timer-dir] [] offline - dsync: updated signature: xxx@xxx.net/Personal
2008-08-02 09:52:29,843 DEBUG [sync-timer-dir] [] offline - dsync: updated signature: xxx@xxx.net/John Kate Marsden
2008-08-02 09:52:29,859 DEBUG [sync-timer-dir] [] offline - dsync: updated signature: xxx@xxx.net/FH Normal
2008-08-02 09:52:30,265 ERROR [sync-timer-dir] [] offline - sync failure: xxx@xxx.net
com.zimbra.common.soap.SoapFaultException: invalid attr name: [LDAP: error code 17 - zimbraPrefCalendarReminderFlashTitle: attribute type undefined]
ExceptionId:btpool0-5049:1217649147365:92e876131bf5d76e
Code:account.INVALID_ATTR_NAME
	at com.zimbra.common.soap.Soap12Protocol.soapFault(Soap12Protocol.java:88)
	at com.zimbra.common.soap.SoapTransport.extractBodyElement(SoapTransport.java:245)
	at com.zimbra.common.soap.SoapTransport.parseSoapResponse(SoapTransport.java:221)
	at com.zimbra.common.soap.SoapHttpTransport.invoke(SoapHttpTransport.java:251)
	at com.zimbra.common.soap.SoapTransport.invoke(SoapTransport.java:297)
	at com.zimbra.cs.zclient.ZMailbox.invoke(ZMailbox.java:526)
	at com.zimbra.cs.zclient.ZMailbox.invoke(ZMailbox.java:520)
	at com.zimbra.cs.zclient.ZMailbox.modifyPrefs(ZMailbox.java:3224)
	at com.zimbra.cs.account.offline.DirectorySync.pushAccount(DirectorySync.java:449)
	at com.zimbra.cs.account.offline.DirectorySync.sync(DirectorySync.java:175)
	at com.zimbra.cs.account.offline.DirectorySync.syncAllAccounts(DirectorySync.java:121)
	at com.zimbra.cs.account.offline.DirectorySync.access$000(DirectorySync.java:54)
	at com.zimbra.cs.account.offline.DirectorySync$1.run(DirectorySync.java:69)
	at java.util.TimerThread.mainLoop(Unknown Source)
	at java.util.TimerThread.run(Unknown Source)
2008-08-02 09:52:30,265 WARN  [sync-timer-dir] [] offline - SoapFaultException: invalid attr name: [LDAP: error code 17 - zimbraPrefCalendarReminderFlashTitle: attribute type undefined]
FaultRequest:
<soap:Envelope xmlns:soap="http://www.w3.org/2003/05/soap-envelope"><soap:Header><context xmlns="urn:zimbra"><authToken>0_c87ec10fbbca4683428f39ddd2ca1d34770e6f2d_69643d33363a30366338396537322d363030622d343861652d393966302d6539623037346134656237623b6578703d31333a313231373737333939383834313b747970653d363a7a696d6272613b6d61696c686f73743d31333a3137322e32302e302e393a38303b</authToken><nosession/><userAgent name="Yahoo! Zimbra Desktop" version="0.90_1251_Windows">0.90_1251_Windows</userAgent><notify seq="0"/></context></soap:Header><soap:Body><ModifyPrefsRequest xmlns="urn:zimbraAccount"><pref name="zimbraPrefMarkMsgRead">3</pref><pref name="zimbraPrefCalendarReminderFlashTitle">FALSE</pref></ModifyPrefsRequest></soap:Body></soap:Envelope>
FaultResponse:
<soap:Envelope xmlns:soap="http://www.w3.org/2003/05/soap-envelope"><soap:Header><context xmlns="urn:zimbra"><change token="141404"/></context></soap:Header><soap:Body><soap:Fault><soap:Code><soap:Value>soap:Sender</soap:Value></soap:Code><soap:Reason><soap:Text>invalid attr name: [LDAP: error code 17 - zimbraPrefCalendarReminderFlashTitle: attribute type undefined]</soap:Text></soap:Reason><soap:Detail><Error xmlns="urn:zimbra"><Code>account.INVALID_ATTR_NAME</Code><Trace>btpool0-5049:1217649147365:92e876131bf5d76e</Trace></Error></soap:Detail></soap:Fault></soap:Body></soap:Envelope>
2008-08-02 09:53:35,500 DEBUG [sync-timer-xxx@xxx.net] [mid=3;] offline - starting delta sync [token 141404]
2008-08-02 09:53:35,500 DEBUG [sync-timer-xxx@xxx.net] [mid=3;] offline - ending delta sync [token 141404]
Is there something I can do to stop this happening?