Description of problem:
No help window

Version-Release number of selected component (if applicable):
eclipse-platform-3.4.0-17.fc10.x86_64

How reproducible:
Always

Steps to Reproduce:
1. Help->Help Contents
  
Actual results:
No help.

Expected results:
Help window.

Additional info:
Log snippet:

java.lang.NoClassDefFoundError: org/eclipse/equinox/http/jetty/JettyConfigurator
        at org.eclipse.help.internal.server.WebappManager.start(WebappManager.java:46)
        at org.eclipse.help.internal.base.BaseHelpSystem.ensureWebappRunning(BaseHelpSystem.java:187)
        at org.eclipse.help.internal.base.HelpDisplay.displayHelpURL(HelpDisplay.java:145)
        at org.eclipse.help.internal.base.HelpDisplay.displayHelp(HelpDisplay.java:39)
        at org.eclipse.help.ui.internal.DefaultHelpUI.displayHelp(DefaultHelpUI.java:127)
        at org.eclipse.ui.internal.help.WorkbenchHelpSystem.displayHelp(WorkbenchHelpSystem.java:833)
        at org.eclipse.ui.internal.actions.HelpContentsAction$1.run(HelpContentsAction.java:83)