We've been in the process of migrating to Zimbra (OSS) over the past couple of weeks. Up to today everything has been going smoothly for the most part, with just a few minor bumps in the road. Today, however, I have been getting a lot of reports of slow response times, server timeouts when deleting, moving and sending messages. This is all with the Zimbra Web Client. We are up to about 125 active users. Server is running 90+% idle, and I'm not seeing any network slow downs. I'm still waiting to get screen shots of some of the error messages the users are getting. I am seeing a lot of the following error messages in the mailbox.log file (not sure if this is related to the client problems or not):

Code:
2007-03-20 12:18:29,572 WARN  [http-443-Processor56] [] [SoapServlet] - Servlet.service() for servlet SoapServlet threw exception
java.net.SocketTimeoutException: Read timed out
        at java.net.SocketInputStream.socketRead0(Native Method)
        at java.net.SocketInputStream.read(SocketInputStream.java:129)
        at com.sun.net.ssl.internal.ssl.InputRecord.readFully(InputRecord.java:293)
        at com.sun.net.ssl.internal.ssl.InputRecord.read(InputRecord.java:331)
        at com.sun.net.ssl.internal.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:723)
        at com.sun.net.ssl.internal.ssl.SSLSocketImpl.readDataRecord(SSLSocketImpl.java:680)
        at com.sun.net.ssl.internal.ssl.AppInputStream.read(AppInputStream.java:75)
        at org.apache.coyote.http11.InternalInputBuffer.fill(InternalInputBuffer.java:747)
        at org.apache.coyote.http11.InternalInputBuffer$InputStreamInputBuffer.doRead(InternalInputBuffer.java:777)
        at org.apache.coyote.http11.filters.IdentityInputFilter.doRead(IdentityInputFilter.java:115)
        at org.apache.coyote.http11.InternalInputBuffer.doRead(InternalInputBuffer.java:712)
        at org.apache.coyote.Request.doRead(Request.java:423)
        at org.apache.catalina.connector.InputBuffer.realReadBytes(InputBuffer.java:283)
        at org.apache.tomcat.util.buf.ByteChunk.substract(ByteChunk.java:404)
        at org.apache.catalina.connector.InputBuffer.read(InputBuffer.java:298)
        at org.apache.catalina.connector.CoyoteInputStream.read(CoyoteInputStream.java:192)
        at com.zimbra.cs.servlet.ZimbraServlet.readFully(ZimbraServlet.java:184)
        at com.zimbra.soap.SoapServlet.doPost(SoapServlet.java:210)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
        at com.zimbra.cs.servlet.ZimbraServlet.service(ZimbraServlet.java:162)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
        at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:541)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
        at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
        at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:667)
        at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
        at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
        at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
        at java.lang.Thread.run(Thread.java:595)
Anyone got any clues on what could be causing these problems, or what else I should be looking for? Hopefully we haven't hit any type of threshold on the server. We've still got another couple hundred users to migrate.