After hudson runs for awhile (a couple of weeks) all my modules fail to build.
To temporarily solve the problem I have to restart hudson; which isn't too fun.
I am running on linux and jdk1.5. This is how I am running hudson: java -jar
hudson.war.

Here is the stacktrace:
ERROR: Failed to parse POMs
hudson.util.IOException2: Cannot start Plexus embedder.
at hudson.maven.MavenModuleSetBuild$PomParser.invoke(MavenModuleSetBuild.java:357)
at hudson.maven.MavenModuleSetBuild$PomParser.invoke(MavenModuleSetBuild.java:296)
at hudson.FilePath.act(FilePath.java:241)
at hudson.maven.MavenModuleSetBuild$RunnerImpl.doRun(MavenModuleSetBuild.java:221)
at hudson.model.AbstractBuild$AbstractRunner.run(AbstractBuild.java:129)
at hudson.model.Run.run(Run.java:562)
at hudson.maven.MavenModuleSetBuild.run(MavenModuleSetBuild.java:159)
at hudson.model.ResourceController.execute(ResourceController.java:66)
at hudson.model.Executor.run(Executor.java:59)
Caused by: org.apache.maven.embedder.MavenEmbedderException: Cannot start Plexus
embedder.
at hudson.maven.MavenEmbedder.start(MavenEmbedder.java:645)
at hudson.maven.MavenUtil.createEmbedder(MavenUtil.java:43)
at hudson.maven.MavenModuleSetBuild$PomParser.invoke(MavenModuleSetBuild.java:337)
... 8 more
Caused by: org.codehaus.plexus.PlexusContainerException: Error starting container
at
org.codehaus.plexus.DefaultPlexusContainer.start(DefaultPlexusContainer.java:787)
at org.codehaus.plexus.embed.Embedder.start(Embedder.java:220)
at org.codehaus.plexus.embed.Embedder.start(Embedder.java:183)
at hudson.maven.MavenEmbedder.start(MavenEmbedder.java:604)
... 10 more
Caused by: org.codehaus.plexus.configuration.PlexusConfigurationException: Error
reading configuration
jar:file:/tmp/winstone/hudson-1.121.war/WEB-INF/lib/maven-profile-2.0.4.jar!/META-INF/plexus/components.xml
at
org.codehaus.plexus.component.discovery.AbstractComponentDiscoverer.findComponents(AbstractComponentDiscoverer.java:89)
at
org.codehaus.plexus.DefaultPlexusContainer.discoverComponents(DefaultPlexusContainer.java:717)
at
org.codehaus.plexus.DefaultPlexusContainer.start(DefaultPlexusContainer.java:779)
... 13 more
Caused by: java.util.zip.ZipException: No such file or directory
at java.util.zip.ZipFile.open(Native Method)
at java.util.zip.ZipFile.<init>(ZipFile.java:203)
at java.util.jar.JarFile.<init>(JarFile.java:132)
at java.util.jar.JarFile.<init>(JarFile.java:70)
at sun.net.www.protocol.jar.URLJarFile.<init>(URLJarFile.java:56)
at sun.net.www.protocol.jar.URLJarFile.getJarFile(URLJarFile.java:41)
at sun.net.www.protocol.jar.JarFileFactory.get(JarFileFactory.java:68)
at sun.net.www.protocol.jar.JarURLConnection.connect(JarURLConnection.java:102)
at
org.codehaus.plexus.component.discovery.AbstractComponentDiscoverer.findComponents(AbstractComponentDiscoverer.java:72)
... 15 more
finished: FAILURE