If your OS is Linux and you are using Eclipse, you might possibly see the following error messages or similar after installing lots of plug-ins in Eclipse. In my case, it usually happened after installing TPTP (I’m using Ubuntu Linux 9.04 Jaunty Jackalope Desktop 64bit by the way).
Plug-in org.eclipse.jst.server.tomcat.core was unable to load class org.eclipse.jst.server.tomcat.core.internal.TomcatLaunchConfigurationDelegate. /eclipse_installed_path/eclipse/configuration/org.eclipse.osgi/.lazy.15 (Too many open files)
Problems occurred while trying to save the state of the workbench. Could not read master table.