"{0}" communication error. Please check port number.

Debug message: Unbuffered entity enclosing request can not be repeated.

Exception:

com.zimbra.common.service.ServiceException: system failure: PushChanges.sync
ExceptionId:sync-mbox-aaa@aaa.com:1272970167853:bb3a2b285a0b9e08
Code:service.FAILURE
at com.zimbra.common.service.ServiceException.FAILURE (ServiceException.java:248)
at com.zimbra.cs.mailbox.SyncExceptionHandler.checkRe coverableException(SyncExceptionHandler.java:55)
at com.zimbra.cs.mailbox.PushChanges.sync(PushChanges .java:296)
at com.zimbra.cs.mailbox.PushChanges.sync(PushChanges .java:182)
at com.zimbra.cs.mailbox.MailboxSync.sync(MailboxSync .java:173)
at com.zimbra.cs.mailbox.ZcsMailbox.sync(ZcsMailbox.j ava:109)
at com.zimbra.cs.mailbox.ZcsMailbox.syncOnTimer(ZcsMa ilbox.java:90)
at com.zimbra.cs.mailbox.SyncMailbox$1.run(SyncMailbo x.java:255)
at java.util.TimerThread.mainLoop(Timer.java:512)
at java.util.TimerThread.run(Timer.java:462)
Caused by: com.zimbra.common.service.ServiceException: resource unreachable: HttpException while fetching http://mail.aaa.com/home/~/Briefcase...fums=1?auth=co
ExceptionId:sync-mbox-aaa@aaa.com:1272970167853:bb3a2b285a0b9e08
Code:service.RESOURCE_UNREACHABLE
at com.zimbra.common.service.ServiceException.RESOURC E_UNREACHABLE(ServiceException.java:270)
at com.zimbra.cs.service.UserServlet.doHttpOp(UserSer vlet.java:1514)
at com.zimbra.cs.service.UserServlet.putMailItem(User Servlet.java:1431)
at com.zimbra.cs.mailbox.ZcsMailbox.sendMailItem(ZcsM ailbox.java:569)
at com.zimbra.cs.mailbox.PushChanges.syncDocument(Pus hChanges.java:974)
at com.zimbra.cs.mailbox.PushChanges.sync(PushChanges .java:293)
... 7 more
Caused by: org.apache.commons.httpclient.ProtocolException: Unbuffered entity enclosing request can not be repeated.
at org.apache.commons.httpclient.methods.EntityEnclos ingMethod.writeRequestBody(EntityEnclosingMethod.j ava:483)
at org.apache.commons.httpclient.HttpMethodBase.write Request(HttpMethodBase.java:1973)
at org.apache.commons.httpclient.HttpMethodBase.execu te(HttpMethodBase.java:993)
at org.apache.commons.httpclient.HttpMethodDirector.e xecuteWithRetry(HttpMethodDirector.java:397)
at org.apache.commons.httpclient.HttpMethodDirector.e xecuteMethod(HttpMethodDirector.java:170)
at org.apache.commons.httpclient.HttpClient.executeMe thod(HttpClient.java:396)
at com.zimbra.common.httpclient.HttpClientUtil.execut eMethod(HttpClientUtil.java:22)
at com.zimbra.common.httpclient.HttpClientUtil.execut eMethod(HttpClientUtil.java:18)
at com.zimbra.cs.service.UserServlet.doHttpOp(UserSer vlet.java:1500)
... 11 more