When trying to upload a zip file to the dms a NoClassDefFoundError exception is thrown:

2009-07-28 15:39:42,270 ERROR se.[Catalina].[localhost].[/magnolia411].[default]: Servlet.service() for servlet default threw exception
java.lang.NoClassDefFoundError: org/apache/tools/zip/ZipFile
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2395)
at java.lang.Class.getDeclaredMethods(Class.java:1763)
at java.beans.Introspector$1.run(Introspector.java:1265)
at java.security.AccessController.doPrivileged(Native Method)
at java.beans.Introspector.getPublicDeclaredMethods(Introspector.java:1263)
at java.beans.Introspector.getTargetMethodInfo(Introspector.java:1129)
at java.beans.Introspector.getBeanInfo(Introspector.java:387)
at java.beans.Introspector.getBeanInfo(Introspector.java:159)
at org.apache.commons.beanutils.PropertyUtilsBean.getPropertyDescriptors(PropertyUtilsBean.java:896)
at org.apache.commons.beanutils.PropertyUtils.getPropertyDescriptors(PropertyUtils.java:326)
at info.magnolia.content2bean.TypeDescriptor.getPropertyDescriptors(TypeDescriptor.java:116)
at info.magnolia.content2bean.impl.Content2BeanProcessorImpl.setProperties(Content2BeanProcessorImpl.java:212)
at info.magnolia.content2bean.impl.Content2BeanProcessorImpl.toBean(Content2BeanProcessorImpl.java:107)
at info.magnolia.content2bean.impl.Content2BeanProcessorImpl.toBean(Content2BeanProcessorImpl.java:75)
at info.magnolia.content2bean.Content2BeanUtil.toBean(Content2BeanUtil.java:151)
at info.magnolia.module.admininterface.PageHandlerManager$RepositoryPageDefinition.newInstance(PageHandlerManager.java:208)
at info.magnolia.module.admininterface.PageHandlerManager.getPageHandler(PageHandlerManager.java:85)
at info.magnolia.module.admininterface.PageMVCServlet.getHandler(PageMVCServlet.java:90)
at info.magnolia.cms.servlets.MVCServlet.doPost(MVCServlet.java:110)
at info.magnolia.cms.servlets.MVCServlet.doGet(MVCServlet.java:68)
.....