A snippet from logs (after adding) :

2008-08-15 12:40:59,453 ERROR [Thread-1] [atlassian.confluence.event.ConfluenceEventManager] publishEvent An exception was encountered while processing the event: com.atlassian.confluence.event.events.admin.ConfluenceReadyEvent[source=com.atlassian.confluence.upgrade.impl.DefaultUpgradeManager@185c6ac]
java.lang.IllegalStateException: Could not init from [ C:\Documents and Settings\Atlassian\confluence-home\bundled-plugins\impresence-plugin-2.2.jar ] due to The filename, directory name, or volume label syntax is incorrect
at com.atlassian.plugin.classloader.PluginClassLoader.<init>(PluginClassLoader.java:51)
at com.atlassian.plugin.loaders.ClassLoadingPluginLoader.deployPluginFromUnit(ClassLoadingPluginLoader.java:89)
at com.atlassian.confluence.plugin.BundledClassLoadingPluginLoader.deployPluginFromUnit(BundledClassLoadingPluginLoader.java:45)
at com.atlassian.plugin.loaders.ClassLoadingPluginLoader.loadAllPlugins(ClassLoadingPluginLoader.java:64)
at com.atlassian.plugin.DefaultPluginManager.init(DefaultPluginManager.java:97)
at com.atlassian.confluence.plugin.ConfluencePluginManager.init(ConfluencePluginManager.java:161)
at com.atlassian.confluence.plugin.ConfluencePluginManager.processConfluenceReadyEvent(ConfluencePluginManager.java:270)
at com.atlassian.confluence.plugin.ConfluencePluginManager.onApplicationEvent(ConfluencePluginManager.java:175)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:304)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:182)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:149)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:106)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at $Proxy5.onApplicationEvent(Unknown Source)
at org.springframework.context.event.SimpleApplicationEventMulticaster$1.run(SimpleApplicationEventMulticaster.java:77)
at org.springframework.core.task.SyncTaskExecutor.execute(SyncTaskExecutor.java:49)
at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:75)
at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:246)
at com.atlassian.event.DefaultEventManager.publishEvent(DefaultEventManager.java:70)
at com.atlassian.confluence.event.ConfluenceEventManager.publishEvent(ConfluenceEventManager.java:19)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:304)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:182)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:149)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:106)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:89)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at $Proxy3.publishEvent(Unknown Source)
at com.atlassian.confluence.upgrade.impl.DefaultUpgradeManager.upgrade(DefaultUpgradeManager.java:75)
at com.atlassian.upgrade.UpgradeLauncherServletContextListener.contextInitialized(UpgradeLauncherServletContextListener.java:26)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3764)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4216)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1014)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:736)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1014)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
at org.apache.catalina.core.StandardService.start(StandardService.java:448)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:700)
at org.apache.catalina.startup.Catalina.start(Catalina.java:552)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:295)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:433)
Caused by: java.io.IOException: The filename, directory name, or volume label syntax is incorrect
at java.io.WinNTFileSystem.createFileExclusively(Native Method)
at java.io.File.checkAndCreate(Unknown Source)
at java.io.File.createTempFile(Unknown Source)
at java.io.File.createTempFile(Unknown Source)
at com.atlassian.plugin.classloader.PluginClassLoader.initialiseInnerJar(PluginClassLoader.java:92)
at com.atlassian.plugin.classloader.PluginClassLoader.initializeFromJar(PluginClassLoader.java:71)
at com.atlassian.plugin.classloader.PluginClassLoader.<init>(PluginClassLoader.java:47)
... 54 more