this is my mailbox.log

2011-08-17 00:00:08,316 WARN [main] [] misc - Could not establish a connection to the database. Retrying in 5 seconds.
com.zimbra.common.service.ServiceException: system failure: getting database connection
ExceptionId:main:1313539208316:4cf79ffc9c6fae6e
Code:service.FAILURE
at com.zimbra.common.service.ServiceException.FAILURE (ServiceException.java:248)
at com.zimbra.cs.db.DbPool.getConnection(DbPool.java: 314)
at com.zimbra.cs.db.DbPool.getConnection(DbPool.java: 278)
at com.zimbra.cs.db.DbPool.waitForDatabase(DbPool.jav a:200)
at com.zimbra.cs.db.DbPool.startup(DbPool.java:191)
at com.zimbra.cs.util.Zimbra.startup(Zimbra.java:157)
at com.zimbra.cs.util.Zimbra.startup(Zimbra.java:123)
at com.zimbra.soap.SoapServlet.init(SoapServlet.java: 128)
at javax.servlet.GenericServlet.init(GenericServlet.j ava:241)
at org.mortbay.jetty.servlet.ServletHolder.initServle t(ServletHolder.java:440)
at org.mortbay.jetty.servlet.ServletHolder.doStart(Se rvletHolder.java:263)
at org.mortbay.component.AbstractLifeCycle.start(Abst ractLifeCycle.java:50)
at org.mortbay.jetty.servlet.ServletHandler.initializ e(ServletHandler.java:685)
at org.mortbay.jetty.servlet.Context.startContext(Con text.java:140)
at org.mortbay.jetty.webapp.WebAppContext.startContex t(WebAppContext.java:1254)
at org.mortbay.jetty.handler.ContextHandler.doStart(C ontextHandler.java:517)
at org.mortbay.jetty.webapp.WebAppContext.doStart(Web AppContext.java:471)
at org.mortbay.component.AbstractLifeCycle.start(Abst ractLifeCycle.java:50)
at org.mortbay.jetty.handler.HandlerCollection.doStar t(HandlerCollection.java:152)
at org.mortbay.jetty.handler.ContextHandlerCollection .doStart(ContextHandlerCollection.java:156)
at org.mortbay.component.AbstractLifeCycle.start(Abst ractLifeCycle.java:50)
at org.mortbay.jetty.handler.HandlerCollection.doStar t(HandlerCollection.java:152)
at org.mortbay.component.AbstractLifeCycle.start(Abst ractLifeCycle.java:50)
at org.mortbay.jetty.handler.HandlerWrapper.doStart(H andlerWrapper.java:130)
at org.mortbay.component.AbstractLifeCycle.start(Abst ractLifeCycle.java:50)
at org.mortbay.jetty.handler.HandlerWrapper.doStart(H andlerWrapper.java:130)
at org.mortbay.jetty.handler.DebugHandler.doStart(Deb ugHandler.java:127)
at org.mortbay.component.AbstractLifeCycle.start(Abst ractLifeCycle.java:50)
at org.mortbay.jetty.handler.HandlerWrapper.doStart(H andlerWrapper.java:130)
at org.mortbay.jetty.Server.doStart(Server.java:224)
at org.mortbay.setuid.SetUIDServer.doStart(SetUIDServ er.java:158)
at org.mortbay.component.AbstractLifeCycle.start(Abst ractLifeCycle.java:50)
at org.mortbay.xml.XmlConfiguration.main(XmlConfigura tion.java:985)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Nativ e Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Native MethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(De legatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.mortbay.start.Main.invokeMain(Main.java:194)
at org.mortbay.start.Main.start(Main.java:534)
at org.mortbay.start.Main.start(Main.java:441)
at org.mortbay.start.Main.main(Main.java:119)
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientC onnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up.
at sun.reflect.GeneratedConstructorAccessor17.newInst ance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newI nstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Construc tor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:40 9)
at com.mysql.jdbc.Util.getInstance(Util.java:384)
at com.mysql.jdbc.SQLError.createSQLException(SQLErro r.java:1015)
at com.mysql.jdbc.SQLError.createSQLException(SQLErro r.java:989)
at com.mysql.jdbc.SQLError.createSQLException(SQLErro r.java:984)
at com.mysql.jdbc.SQLError.createSQLException(SQLErro r.java:929)
at com.mysql.jdbc.ConnectionImpl.connectWithRetries(C onnectionImpl.java:2226)
at com.mysql.jdbc.ConnectionImpl.createNewIO(Connecti onImpl.java:2127)
at com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:774)
at com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:49)
at sun.reflect.GeneratedConstructorAccessor15.newInst ance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newI nstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Construc tor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:40 9)

at com.mysql.jdbc.ConnectionImpl.getInstance(Connecti onImpl.java:375)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonReg isteringDriver.java:289)
at java.sql.DriverManager.getConnection(DriverManager .java:582)
at java.sql.DriverManager.getConnection(DriverManager .java:154)
at org.apache.commons.dbcp.DriverManagerConnectionFac tory.createConnection(DriverManagerConnectionFacto ry.java:78)
at com.zimbra.cs.db.ZimbraConnectionFactory.createCon nection(ZimbraConnectionFactory.java:66)
at org.apache.commons.dbcp.PoolableConnectionFactory. makeObject(PoolableConnectionFactory.java:582)
at org.apache.commons.pool.impl.GenericObjectPool.bor rowObject(GenericObjectPool.java:1158)
at org.apache.commons.dbcp.PoolingDataSource.getConne ction(PoolingDataSource.java:106)
at com.zimbra.cs.db.DbPool.getConnection(DbPool.java: 295)
... 39 more
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsExce ption: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.GeneratedConstructorAccessor12.newInst ance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newI nstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Construc tor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:40 9)
at com.mysql.jdbc.SQLError.createCommunicationsExcept ion(SQLError.java:1118)
at com.mysql.jdbc.MysqlIO.(MysqlIO.java:343)
at com.mysql.jdbc.ConnectionImpl.connectWithRetries(C onnectionImpl.java:2168)
... 56 more
Caused by: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(PlainSocketImpl .java:351)
at java.net.PlainSocketImpl.connectToAddress(PlainSoc ketImpl.java:213)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.j ava:200)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.j ava:366)
at java.net.Socket.connect(Socket.java:529)
at java.net.Socket.connect(Socket.java:478)
at java.net.Socket.(Socket.java:375)
at java.net.Socket.(Socket.java:218)
at com.mysql.jdbc.StandardSocketFactory.connect(Stand ardSocketFactory.java:256)
at com.mysql.jdbc.MysqlIO.(MysqlIO.java:292)
... 57 more
2011-08-17 00:00:32,785 WARN [main] [] misc - Could not establish a connection to the database. Retrying in 5 seconds.
com.zimbra.common.service.ServiceException: system failure: getting database connection
ExceptionId:main:1313539232785:4cf79ffc9c6fae6e