I see someone else posted this error back in October with no responses:

Product name: Zimbra Desktop
Product version: 7.1.2
Build ID: 10978
Release type: GA
OS Platform: Mac OS X i386 10.6.8
Time of event: 2011-11-21 11:04:42
Error type: zclient.IO_ERROR
Item ID: 1
Error summary: Sync failed due to IOException for the following items
Items will be retried on next sync
Item Id: 1073741942 Message: PushChanges.sync


Failure details - PLEASE REMOVE ANY SENSITIVE INFORMATION
----------------------------------------------------------------------------

com.zimbra.common.zclient.ZClientException: The server core.stratfor.com failed to respond
ExceptionId:sync-mbox-user@domain:1321895082594:852eb3b47d6ef7b4
Code:zclient.IO_ERROR
at com.zimbra.common.zclient.ZClientException.IO_ERRO R(ZClientException.java:45)
at com.zimbra.cs.zclient.ZMailbox.uploadContentAsStre am(ZMailbox.java:1906)
at com.zimbra.cs.mailbox.PushChanges.uploadMessage(Pu shChanges.java:468)
at com.zimbra.cs.mailbox.PushChanges.syncMessage(Push Changes.java:1212)
at com.zimbra.cs.mailbox.PushChanges.sync(PushChanges .java:303)
at com.zimbra.cs.mailbox.PushChanges.sync(PushChanges .java:193)
at com.zimbra.cs.mailbox.MailboxSync.sync(MailboxSync .java:168)
at com.zimbra.cs.mailbox.ZcsMailbox.sync(ZcsMailbox.j ava:121)
at com.zimbra.cs.mailbox.ZcsMailbox.syncOnTimer(ZcsMa ilbox.java:102)
at com.zimbra.cs.mailbox.SyncMailbox$1.run(SyncMailbo x.java:257)
at java.util.TimerThread.mainLoop(Timer.java:512)
at java.util.TimerThread.run(Timer.java:462)
Caused by: org.apache.commons.httpclient.NoHttpResponseExcept ion: The server xxxmailserverinfoxx failed to respond
at org.apache.commons.httpclient.HttpMethodBase.readS tatusLine(HttpMethodBase.java:1976)
at org.apache.commons.httpclient.HttpMethodBase.readR esponse(HttpMethodBase.java:1735)
at org.apache.commons.httpclient.HttpMethodBase.execu te(HttpMethodBase.java:1098)
at org.apache.commons.httpclient.HttpMethodDirector.e xecuteWithRetry(HttpMethodDirector.java:398)
at org.apache.commons.httpclient.HttpMethodDirector.e xecuteMethod(HttpMethodDirector.java:171)
at org.apache.commons.httpclient.HttpClient.executeMe thod(HttpClient.java:397)
at com.zimbra.common.httpclient.HttpClientUtil.execut eMethod(HttpClientUtil.java:55)
at com.zimbra.common.httpclient.HttpClientUtil.execut eMethod(HttpClientUtil.java:41)
at com.zimbra.cs.zclient.ZMailbox.uploadContentAsStre am(ZMailbox.java:1896)
... 10 more


Is it possible to have a developer look at this and give me an idea as to what may be causing this?

Thank you

Doug