Install Force.com IDE on Eclipse 4.2 (Juno)

• Use this Force.com IDE Update site http://www.adnsandbox.com/tools/ide/install/
• Copy org.eclipse.update.ui_3.2.300.v20100512.jar to the eclipse/plugins directory. Get this file from the old version of Eclipse or from this site http://www.java2s.com/Code/Jar/o/Downloadorgeclipseupdateui32300v20100512jar.htm. If this file is missing, we will get the following error message:-

Cannot complete the install because one or more required items could not be found.
  Software being installed: Force.com IDE 27.0.0.201302151147 (com.salesforce.ide.feature.feature.group 27.0.0.201302151147)
  Missing requirement: Force.com IDE 27.0.0.201302151147 (com.salesforce.ide.feature.feature.group 27.0.0.201302151147) requires 'org.eclipse.update.ui 0.0.0' but it could not be found

Refs

• http://wiki.developerforce.com/page/Force.com_IDE_Installation_for_Eclipse_3.6
• http://boards.developerforce.com/t5/General-Development/Install-Eclipse-Juno-4-2-with-Force-com-IDE/td-p/462323