This seems to have broken the builds kicking off by timer

Exception: java.lang.NoClassDefFoundError: hudson/plugins/timestamper/TimestamperBuildWrapper

Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.blockbuild.BlockBuildWhenDownstreamBuildingBoolSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.blockbuild.BlockBuildWhenUpstreamBuildingBoolSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: NOT Loaded: class configurationslicing.buildtimeout.BuildTimeoutSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.customworkspace.CustomWorkspaceStringSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.email.CoreEmailSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: NOT Loaded: class configurationslicing.email.ExtEmailSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: NOT Loaded: class configurationslicing.executeshell.ExecuteJythonSlicerWrapper
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: NOT Loaded: class configurationslicing.executeshell.ExecutePythonSlicerWrapper
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.executeshell.ExecuteShellSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.executeshell.ExecuteWindowsBatchSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.executeshell.MavenTargetsSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.jdk.JdkSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.jobdisabled.JobDisabledBoolSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.jobdisabled.JobDisabledStringSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.label.LabelSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.logrotator.LogRotationSlicer$ArtifactBuilds
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.logrotator.LogRotationSlicer$ArtifactDays
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.logrotator.LogRotationSlicer$Count
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.logrotator.LogRotationSlicer$Days
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.maven.MavenGoals
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.maven.MavenOptsSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.maven.MavenVersionSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.parameters.ParametersSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: NOT Loaded: class configurationslicing.prioritysorter.PrioritySorterSlicerWrapper
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.timer.SCMTimerSliceStringSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.timer.TimerSliceStringSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.timestamper.TimestamperSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.tools.AntSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: NOT Loaded: class configurationslicing.tools.GradleSlicerWrapper
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: NOT Loaded: class configurationslicing.tools.GroovySlicerWrapper
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.wscleanup.CleanupAfterSlicer
Feb 18, 2013 11:24:24 PM configurationslicing.ConfigurationSlicing getAxes
INFO: Loaded: class configurationslicing.wscleanup.CleanupBeforeSlicer
Feb 18, 2013 11:24:24 PM winstone.Logger logInternal
SEVERE: Error while serving http://jenkins001.company.com:8080/slicing/timestamper
java.lang.reflect.InvocationTargetException
at sun.reflect.GeneratedMethodAccessor1040.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:288)
at org.kohsuke.stapler.Function.bindAndInvoke(Function.java:151)
at org.kohsuke.stapler.MetaClass$12.dispatch(MetaClass.java:382)
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:573)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:658)
at org.kohsuke.stapler.MetaClass$12.dispatch(MetaClass.java:384)
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:573)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:658)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:487)
at org.kohsuke.stapler.Stapler.service(Stapler.java:164)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:45)
at winstone.ServletConfiguration.execute(ServletConfiguration.java:248)
at winstone.RequestDispatcher.forward(RequestDispatcher.java:333)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:376)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:95)
at net.bull.javamelody.MonitoringFilter.doFilter(MonitoringFilter.java:206)
at net.bull.javamelody.MonitoringFilter.doFilter(MonitoringFilter.java:179)
at net.bull.javamelody.PluginMonitoringFilter.doFilter(PluginMonitoringFilter.java:86)
at org.jvnet.hudson.plugins.monitoring.HudsonMonitoringFilter.doFilter(HudsonMonitoringFilter.java:84)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:98)
at hudson.plugins.greenballs.GreenBallFilter.doFilter(GreenBallFilter.java:58)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:98)
at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:87)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:47)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:84)
at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)
at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:164)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:50)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at hudson.util.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:81)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at winstone.RequestDispatcher.forward(RequestDispatcher.java:331)
at winstone.RequestHandlerThread.processRequest(RequestHandlerThread.java:215)
at winstone.RequestHandlerThread.run(RequestHandlerThread.java:138)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:439)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at winstone.BoundedExecutorService$1.run(BoundedExecutorService.java:77)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:662)
Caused by: java.lang.NoClassDefFoundError: hudson/plugins/timestamper/TimestamperBuildWrapper
at configurationslicing.timestamper.TimestamperSlicer$TimestamperSliceSpec.getValues(TimestamperSlicer.java:56)
at configurationslicing.timestamper.TimestamperSlicer$TimestamperSliceSpec.getValues(TimestamperSlicer.java:25)
at configurationslicing.UnorderedStringSlicer.accumulate(UnorderedStringSlicer.java:72)
at configurationslicing.UnorderedStringSlicer.accumulate(UnorderedStringSlicer.java:6)
at configurationslicing.ConfigurationSlicing$SliceExecutor.execute(ConfigurationSlicing.java:125)
at configurationslicing.ConfigurationSlicing$SliceExecutor.<init>(ConfigurationSlicing.java:113)
at configurationslicing.ConfigurationSlicing.getDynamic(ConfigurationSlicing.java:98)
... 52 more
Feb 18, 2013 11:24:24 PM org.kohsuke.stapler.compression.CompressionFilter reportException
WARNING: Untrapped servlet exception
javax.servlet.ServletException: java.lang.NoClassDefFoundError: hudson/plugins/timestamper/TimestamperBuildWrapper
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:615)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:658)
at org.kohsuke.stapler.MetaClass$12.dispatch(MetaClass.java:384)
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:573)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:658)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:487)
at org.kohsuke.stapler.Stapler.service(Stapler.java:164)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:45)
at winstone.ServletConfiguration.execute(ServletConfiguration.java:248)
at winstone.RequestDispatcher.forward(RequestDispatcher.java:333)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:376)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:95)
at net.bull.javamelody.MonitoringFilter.doFilter(MonitoringFilter.java:206)
at net.bull.javamelody.MonitoringFilter.doFilter(MonitoringFilter.java:179)
at net.bull.javamelody.PluginMonitoringFilter.doFilter(PluginMonitoringFilter.java:86)
at org.jvnet.hudson.plugins.monitoring.HudsonMonitoringFilter.doFilter(HudsonMonitoringFilter.java:84)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:98)
at hudson.plugins.greenballs.GreenBallFilter.doFilter(GreenBallFilter.java:58)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:98)
at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:87)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:47)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:84)
at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)
at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:164)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:50)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at hudson.util.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:81)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:194)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:366)
at winstone.RequestDispatcher.forward(RequestDispatcher.java:331)
at winstone.RequestHandlerThread.processRequest(RequestHandlerThread.java:215)
at winstone.RequestHandlerThread.run(RequestHandlerThread.java:138)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:439)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at winstone.BoundedExecutorService$1.run(BoundedExecutorService.java:77)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:662)
Caused by: java.lang.NoClassDefFoundError: hudson/plugins/timestamper/TimestamperBuildWrapper
at configurationslicing.timestamper.TimestamperSlicer$TimestamperSliceSpec.getValues(TimestamperSlicer.java:56)
at configurationslicing.timestamper.TimestamperSlicer$TimestamperSliceSpec.getValues(TimestamperSlicer.java:25)
at configurationslicing.UnorderedStringSlicer.accumulate(UnorderedStringSlicer.java:72)
at configurationslicing.UnorderedStringSlicer.accumulate(UnorderedStringSlicer.java:6)
at configurationslicing.ConfigurationSlicing$SliceExecutor.execute(ConfigurationSlicing.java:125)
at configurationslicing.ConfigurationSlicing$SliceExecutor.<init>(ConfigurationSlicing.java:113)
at configurationslicing.ConfigurationSlicing.getDynamic(ConfigurationSlicing.java:98)
at sun.reflect.GeneratedMethodAccessor1040.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:288)
at org.kohsuke.stapler.Function.bindAndInvoke(Function.java:151)
at org.kohsuke.stapler.MetaClass$12.dispatch(MetaClass.java:382)
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:573)
... 45 more