ZD fails to push changes to Zimbra Server

[turbomettwurst]

I'm running into this little error, iirc correctly it started when i installed and used ZD on MacOSX, now none of my Desktop Clients sync (2x Linux, 1 OSX) sync properly

2009-02-16 13:12:49,477 DEBUG [btpool0-2] [mid=5;] offline - starting change push
2009-02-16 13:12:49,503 ERROR [btpool0-2] [mid=5;] offline - sync failure: as@____.de
com.zimbra.common.service.ServiceException: system failure: PushChanges.sync
ExceptionId:btpool0-2:1234786369503:68de7c3bc6bfaf93
Code:service.FAILURE
    at com.zimbra.common.service.ServiceException.FAILURE(ServiceException.java:253)
    at com.zimbra.cs.mailbox.SyncExceptionHandler.checkRecoverableException(SyncExceptionHandler.java:40)
    at com.zimbra.cs.mailbox.PushChanges.sync(PushChanges.java:373)
    at com.zimbra.cs.mailbox.PushChanges.sync(PushChanges.java:174)
    at com.zimbra.cs.mailbox.MailboxSync.sync(MailboxSync.java:185)
    at com.zimbra.cs.mailbox.OfflineMailbox.sync(OfflineMailbox.java:140)
    at com.zimbra.cs.service.offline.OfflineSync.handle(OfflineSync.java:47)
    at com.zimbra.soap.SoapEngine.dispatchRequest(SoapEngine.java:429)
    at com.zimbra.soap.SoapEngine.dispatch(SoapEngine.java:286)
    at com.zimbra.soap.SoapEngine.dispatch(SoapEngine.java:160)
    at com.zimbra.soap.SoapServlet.doPost(SoapServlet.java:269)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
    at com.zimbra.cs.servlet.ZimbraServlet.service(ZimbraServlet.java:190)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
    at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:487)
    at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:362)
    at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
    at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:181)
    at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:716)
    at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:406)
    at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:211)
    at org.mortbay.jetty.handler.HandlerCollection.handle(HandlerCollection.java:114)
    at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:139)
    at org.mortbay.jetty.handler.RewriteHandler.handle(RewriteHandler.java:176)
    at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:139)
    at org.mortbay.jetty.Server.handle(Server.java:313)
    at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:506)
    at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:844)
    at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:644)
    at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:211)
    at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:381)
    at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:396)
    at org.mortbay.thread.BoundedThreadPool$PoolThread.run(BoundedThreadPool.java:442)
Caused by: com.zimbra.common.service.ServiceException: resource unreachable: Internal Server Error
ExceptionId:btpool0-2:1234786369503:68de7c3bc6bfaf93
Code:service.RESOURCE_UNREACHABLE
    at com.zimbra.common.service.ServiceException.RESOURCE_UNREACHABLE(ServiceException.java:275)
    at com.zimbra.cs.service.UserServlet.doHttpOp(UserServlet.java:1446)
    at com.zimbra.cs.service.UserServlet.putMailItem(UserServlet.java:1368)
    at com.zimbra.cs.mailbox.OfflineMailbox.sendMailItem(OfflineMailbox.java:812)
    at com.zimbra.cs.mailbox.PushChanges.syncDocument(PushChanges.java:1069)
    at com.zimbra.cs.mailbox.PushChanges.sync(PushChanges.java:370)
    ... 30 more