"Invalid state, the Connection object is closed." with JTDS 1.2 and MSSQL 2000

After a time (log entries attached) with no connections, JIRA is not accessible until I restart the Tomcat service. The first exception in the log is:

2006-01-26 21:51:19,690 INFO [jira.action.admin.DataExport] Export took 2250ms
2006-01-26 21:51:19,690 INFO [jira.action.admin.DataExport] Wrote 19006 entities to export
2006-01-27 08:32:25,670 ERROR [user.provider.ofbiz.OFBizAccessProvider] GenericEntityException: org.ofbiz.core.entity.GenericDataSourceException: SQL Exception while executing the following:SELECT ID, username, PASSWORD_HASH FROM userbase WHERE username=? (Invalid state, the Connection object is closed.)
org.ofbiz.core.entity.GenericDataSourceException: SQL Exception while executing the following:SELECT ID, username, PASSWORD_HASH FROM userbase WHERE username=? (Invalid state, the Connection object is closed.)
at org.ofbiz.core.entity.jdbc.SQLProcessor.prepareStatement(SQLProcessor.java:330)
at org.ofbiz.core.entity.GenericDAO.selectListIteratorByCondition(GenericDAO.java:1024)
at org.ofbiz.core.entity.GenericDAO.selectByAnd(GenericDAO.java:595)
at org.ofbiz.core.entity.GenericHelperDAO.findByAnd(GenericHelperDAO.java:134)
at org.ofbiz.core.entity.GenericDelegator.findByAnd(GenericDelegator.java:782)
at org.ofbiz.core.entity.GenericDelegator.findByAnd(GenericDelegator.java:767)
at org.ofbiz.core.entity.GenericDelegator.findByAnd(GenericDelegator.java:744)
at com.opensymphony.user.provider.ofbiz.OFBizAbstractProvider.findUser(OFBizAbstractProvider.java:156)
at com.opensymphony.user.provider.ofbiz.OFBizAccessProvider.handles(OFBizAccessProvider.java:116)
at com.opensymphony.user.UserManager.getProvider(UserManager.java:275)
at com.opensymphony.user.UserManager$Accessor.getAccessProvider(UserManager.java:392)
at com.opensymphony.user.Entity.getAccessProvider(Entity.java:100)
at com.opensymphony.user.User.getGroups(User.java:91)
at com.atlassian.jira.security.DefaultGlobalPermissionManager.hasPermission(DefaultGlobalPermissionManager.java:161)
at com.atlassian.jira.security.AbstractPermissionManager.hasPermission(AbstractPermissionManager.java:85)
at sun.reflect.GeneratedMethodAccessor56.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.atlassian.util.profiling.object.ObjectProfiler.profiledInvoke(ObjectProfiler.java:71)
at com.atlassian.jira.config.component.SwitchingInvocationHandler.invoke(SwitchingInvocationHandler.java:28)
at $Proxy1.hasPermission(Unknown Source)
at com.atlassian.jira.security.JiraRoleMapper.canLogin(JiraRoleMapper.java:32)
at com.atlassian.seraph.auth.DefaultAuthenticator.login(DefaultAuthenticator.java:99)
at com.atlassian.seraph.filter.LoginFilter.doFilter(LoginFilter.java:125)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.util.profiling.filters.ProfilingFilter.doFilter(ProfilingFilter.java:132)
at com.atlassian.jira.web.filters.ProfilingAndErrorFilter.doFilter(ProfilingAndErrorFilter.java:25)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.jira.web.filters.ActionCleanupDelayFilter.doFilter(ActionCleanupDelayFilter.java:37)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.johnson.filters.JohnsonFilter.doFilter(JohnsonFilter.java:91)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.jira.web.filters.gzip.GzipFilter.doFilter(GzipFilter.java:72)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.core.filters.AbstractEncodingFilter.doFilter(AbstractEncodingFilter.java:37)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
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.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:856)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:744)
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$ControlRunnable.run(ThreadPool.java:684)
at java.lang.Thread.run(Unknown Source)
java.sql.SQLException: Invalid state, the Connection object is closed.
at net.sourceforge.jtds.jdbc.ConnectionJDBC2.checkOpen(ConnectionJDBC2.java:1494)
at net.sourceforge.jtds.jdbc.ConnectionJDBC2.prepareStatement(ConnectionJDBC2.java:2215)
at org.apache.tomcat.dbcp.dbcp.DelegatingConnection.prepareStatement(DelegatingConnection.java:199)
at org.apache.tomcat.dbcp.dbcp.PoolingDataSource$PoolGuardConnectionWrapper.prepareStatement(PoolingDataSource.java:283)
at org.ofbiz.core.entity.jdbc.SQLProcessor.prepareStatement(SQLProcessor.java:325)
at org.ofbiz.core.entity.GenericDAO.selectListIteratorByCondition(GenericDAO.java:1024)
at org.ofbiz.core.entity.GenericDAO.selectByAnd(GenericDAO.java:595)
at org.ofbiz.core.entity.GenericHelperDAO.findByAnd(GenericHelperDAO.java:134)
at org.ofbiz.core.entity.GenericDelegator.findByAnd(GenericDelegator.java:782)
at org.ofbiz.core.entity.GenericDelegator.findByAnd(GenericDelegator.java:767)
at org.ofbiz.core.entity.GenericDelegator.findByAnd(GenericDelegator.java:744)
at com.opensymphony.user.provider.ofbiz.OFBizAbstractProvider.findUser(OFBizAbstractProvider.java:156)
at com.opensymphony.user.provider.ofbiz.OFBizAccessProvider.handles(OFBizAccessProvider.java:116)
at com.opensymphony.user.UserManager.getProvider(UserManager.java:275)
at com.opensymphony.user.UserManager$Accessor.getAccessProvider(UserManager.java:392)
at com.opensymphony.user.Entity.getAccessProvider(Entity.java:100)
at com.opensymphony.user.User.getGroups(User.java:91)
at com.atlassian.jira.security.DefaultGlobalPermissionManager.hasPermission(DefaultGlobalPermissionManager.java:161)
at com.atlassian.jira.security.AbstractPermissionManager.hasPermission(AbstractPermissionManager.java:85)
at sun.reflect.GeneratedMethodAccessor56.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.atlassian.util.profiling.object.ObjectProfiler.profiledInvoke(ObjectProfiler.java:71)
at com.atlassian.jira.config.component.SwitchingInvocationHandler.invoke(SwitchingInvocationHandler.java:28)
at $Proxy1.hasPermission(Unknown Source)
at com.atlassian.jira.security.JiraRoleMapper.canLogin(JiraRoleMapper.java:32)
at com.atlassian.seraph.auth.DefaultAuthenticator.login(DefaultAuthenticator.java:99)
at com.atlassian.seraph.filter.LoginFilter.doFilter(LoginFilter.java:125)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.util.profiling.filters.ProfilingFilter.doFilter(ProfilingFilter.java:132)
at com.atlassian.jira.web.filters.ProfilingAndErrorFilter.doFilter(ProfilingAndErrorFilter.java:25)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.jira.web.filters.ActionCleanupDelayFilter.doFilter(ActionCleanupDelayFilter.java:37)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.johnson.filters.JohnsonFilter.doFilter(JohnsonFilter.java:91)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.jira.web.filters.gzip.GzipFilter.doFilter(GzipFilter.java:72)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.core.filters.AbstractEncodingFilter.doFilter(AbstractEncodingFilter.java:37)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
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.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:856)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:744)
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(Unknown Source)

And then pretty much any request after that results in a "Invalid state, the Connection object is closed." error and JIRA hangs. This might be related to JRA-6796 but I'm not sure.